Todas as Publicações do INCT-MI – INCT – Institutos Nacionais de Ciência e Tecnologia

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1.
Pedro Ivo R. Moraes Márcio F. Santos, Sérgio R. Tavares
Analysis of the energy and nature of bandgap in layered double hydroxides Mg-Al-X and Zn-Al-X (X= Cl , OH , CO , or NO ) Working paper
2026.
Resumo | Links | BibTeX | Tags:
@workingpaper{nokey,
title = {Analysis of the energy and nature of bandgap in layered double hydroxides Mg-Al-X and Zn-Al-X (X= Cl , OH , CO , or NO )},
author = {Márcio F. Santos, Pedro Ivo R. Moraes, Sérgio R. Tavares, A.S. Martins, Rodrigo B. Capaz,
Fernando Wypych, Alexandre A. Leitão},
doi = {https://doi.org/10.1016/j.clay.2025.108061},
year = {2026},
date = {2026-01-02},
abstract = {Photocatalysts are materials activated by sunlight and are therefore in line with so-called “Green Chemistry”. However, ab initio calculations based on Density Functional Theory (DFT) fail to describe the bandgap, which is a fundamental parameter in photocatalysis. Therefore, more sophisticated tools were required to estimate the energy bandgap and construct the band structure of the materials studied. This study expanded the electron’s self-energy in terms of the single particle Green’s function and the screened Coulomb interaction (GW approximation), evaluating how the bandgap behaves when intercalated anions are exchanged and when the ratio M and M cations in the structure of layered double hydroxides (LDH). The calculations demonstrated that the forbidden band in layered double hydroxides can be tuned by varying the composition of the layers, as well as of the intercalated anions. This study suggests that LDH can be designed with finely tuned bandgaps for environmental and economic goals, such as CO photoreduction by sunlight, as well as organic pollutant decomposition.},
keywords = {},
pubstate = {published},
tppubtype = {workingpaper}
}

Fechar
Photocatalysts are materials activated by sunlight and are therefore in line with so-called “Green Chemistry”. However, ab initio calculations based on Density Functional Theory (DFT) fail to describe the bandgap, which is a fundamental parameter in photocatalysis. Therefore, more sophisticated tools were required to estimate the energy bandgap and construct the band structure of the materials studied. This study expanded the electron’s self-energy in terms of the single particle Green’s function and the screened Coulomb interaction (GW approximation), evaluating how the bandgap behaves when intercalated anions are exchanged and when the ratio M and M cations in the structure of layered double hydroxides (LDH). The calculations demonstrated that the forbidden band in layered double hydroxides can be tuned by varying the composition of the layers, as well as of the intercalated anions. This study suggests that LDH can be designed with finely tuned bandgaps for environmental and economic goals, such as CO photoreduction by sunlight, as well as organic pollutant decomposition.
Fechar
doi:https://doi.org/10.1016/j.clay.2025.108061
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2.
Oliveira, Caique C.; Autreto, Pedro A. S.
Strain-Engineered Jacutingaite Analogs as Efficient 2D Catalysts for Hydrogen Evolution Reactions Journal Article
Em: ACS Omega, 2025, ISSN: 2470-1343.
Resumo | Links | BibTeX | Tags:
@article{Oliveira2025c,
title = {Strain-Engineered Jacutingaite Analogs as Efficient 2D Catalysts for Hydrogen Evolution Reactions},
author = {Caique C. Oliveira and Pedro A. S. Autreto},
doi = {10.1021/acsomega.5c09065},
issn = {2470-1343},
year = {2025},
date = {2025-11-28},
urldate = {2025-11-28},
journal = {ACS Omega},
publisher = {American Chemical Society (ACS)},
abstract = {The catalytic properties of Pt2XSe3 (X = Hg, Zn) for Hydrogen Evolution Reactions (HER) have been investigated based on state-of-the-art ab initio simulations. Our findings indicate that the late transition metal sites (Hg and Zn) demonstrate superior activity for HER under acidic conditions. Moreover, lattice stretching or compression can significantly influence the H binding energy, achieving near-thermoneutral adsorption at a 3% compressive strain. This effect is attributed to the alterations in the d-band centers of late transition metal (X) sites and changes in the bonding strength, demonstrated by the changes in the integrated Crystal Orbital Hamilton Population (ICOHP). Furthermore, charge difference analysis reveals how charge accumulation between the X and Pt atoms changes as the structure is stretched (tensile strain), weakening the interactions with the H adsorbate due to the increased electrostatic repulsion. Our contribution explores strain engineering as an effective approach to tailor the catalytic activity of 2D materials for HER by providing insights into the role of mechanical manipulation in altering electronic properties and boosting catalytic performance.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}

Fechar
The catalytic properties of Pt2XSe3 (X = Hg, Zn) for Hydrogen Evolution Reactions (HER) have been investigated based on state-of-the-art ab initio simulations. Our findings indicate that the late transition metal sites (Hg and Zn) demonstrate superior activity for HER under acidic conditions. Moreover, lattice stretching or compression can significantly influence the H binding energy, achieving near-thermoneutral adsorption at a 3% compressive strain. This effect is attributed to the alterations in the d-band centers of late transition metal (X) sites and changes in the bonding strength, demonstrated by the changes in the integrated Crystal Orbital Hamilton Population (ICOHP). Furthermore, charge difference analysis reveals how charge accumulation between the X and Pt atoms changes as the structure is stretched (tensile strain), weakening the interactions with the H adsorbate due to the increased electrostatic repulsion. Our contribution explores strain engineering as an effective approach to tailor the catalytic activity of 2D materials for HER by providing insights into the role of mechanical manipulation in altering electronic properties and boosting catalytic performance.
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doi:10.1021/acsomega.5c09065
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3.
Torres, Alberto; de Oliveira, Alan Barros; dos Santos Barbosa, Mathus; Lelovsky, Leonardo Villegas; Resende, Valdirene; Dutra, Flávio; Pimenta, Felipe; Parreira, Fabricio; de Mello Souza, Amaury; Matos, Matheus Josué Souza; Rocha, Alexandre Reily
Machine learning interatomic potential for the structural properties iron oxides Não publicado
Research Square, 2025.
Resumo | Links | BibTeX | Tags:
@unpublished{Torres2025,
title = {Machine learning interatomic potential for the structural properties iron oxides},
author = {Alberto Torres and Alan Barros de Oliveira and Mathus dos Santos Barbosa and Leonardo Villegas Lelovsky and Valdirene Resende and Flávio Dutra and Felipe Pimenta and Fabricio Parreira and Amaury de Mello Souza and Matheus Josué Souza Matos and Alexandre Reily Rocha},
url = {https://www.researchsquare.com/article/rs-8031034/v1},
doi = {10.21203/rs.3.rs-8031034/v1},
year = {2025},
date = {2025-11-25},
urldate = {2025-11-25},
publisher = {Springer Science and Business Media LLC},
abstract = {Abstract

Iron oxides constitute an important class of materials, exhibiting a rich and intricate range of behaviors. Despite their significance, the structural and mechanical properties, particularly of Hematite ($alpha$-Fe2O3), have been scarcely investigated in the literature. At the same time, recent developments in machine learning for interatomic potentials have revolutionized computational materials science by enabling highly accurate and efficient simulations of atomic interactions. Traditional methods, such as density functional theory (DFT) and classical force fields, often struggle with high computational costs or lack the flexibility to generalize across diverse chemical environments. ML-based approaches have emerged as powerful alternatives, learning complex potential energy surfaces from quantum-mechanical data. These models can achieve DFT accuracy at a fraction of the computational cost, facilitating large-scale molecular dynamics (MD) simulations.
In this work, we present a graph neural network interatomic potential for hematite. The model was trained on datasets generated from DFT+U calculations to account for strong electronic correlations, using atomic configurations sampled across a wide range of temperatures and pressures. Our potential accurately reproduces fundamental material properties, including the elastic moduli, anisotropic elastic constants, vibrational frequencies, and surface energies. Furthermore, we demonstrate its transferability to other bulk iron oxides. This work enables large-scale molecular dynamics (MD) simulations of iron-based materials with ab initio accuracy at a computational cost comparable to that of classical potentials, opening new opportunities for investigating these complex systems.
},
howpublished = {Research Square},
keywords = {},
pubstate = {published},
tppubtype = {unpublished}
}

Fechar
<title>Abstract</title>
<p>Iron oxides constitute an important class of materials, exhibiting a rich and intricate range of behaviors. Despite their significance, the structural and mechanical properties, particularly of Hematite ($alpha$-Fe2O3), have been scarcely investigated in the literature. At the same time, recent developments in machine learning for interatomic potentials have revolutionized computational materials science by enabling highly accurate and efficient simulations of atomic interactions. Traditional methods, such as density functional theory (DFT) and classical force fields, often struggle with high computational costs or lack the flexibility to generalize across diverse chemical environments. ML-based approaches have emerged as powerful alternatives, learning complex potential energy surfaces from quantum-mechanical data. These models can achieve DFT accuracy at a fraction of the computational cost, facilitating large-scale molecular dynamics (MD) simulations.
In this work, we present a graph neural network interatomic potential for hematite. The model was trained on datasets generated from DFT+U calculations to account for strong electronic correlations, using atomic configurations sampled across a wide range of temperatures and pressures. Our potential accurately reproduces fundamental material properties, including the elastic moduli, anisotropic elastic constants, vibrational frequencies, and surface energies. Furthermore, we demonstrate its transferability to other bulk iron oxides. This work enables large-scale molecular dynamics (MD) simulations of iron-based materials with ab initio accuracy at a computational cost comparable to that of classical potentials, opening new opportunities for investigating these complex systems.</p>
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https://www.researchsquare.com/article/rs-8031034/v1
doi:10.21203/rs.3.rs-8031034/v1
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4.
Paramasivam, Sathish Kumar; Perali, Andrea; Milošević, Milorad V.
Berezinskii-Kosterlitz-Thouless transition with enhanced phase stiffness in $d$-wave strongly coupled two-dimensional superconductors Miscellaneous
2025.
Resumo | Links | BibTeX | Tags:
@misc{paramasivam2025berezinskiikosterlitzthoulesstransitionenhancedphase,
title = {Berezinskii-Kosterlitz-Thouless transition with enhanced phase stiffness in $d$-wave strongly coupled two-dimensional superconductors},
author = {Sathish Kumar Paramasivam and Andrea Perali and Milorad V. Milošević},
url = {https://arxiv.org/abs/2511.16385},
year = {2025},
date = {2025-11-20},
urldate = {2025-01-01},
abstract = {We reveal the key role of the d-wave symmetry of the superconducting gap in strongly coupled two-dimensional (2D) superconductors in determining the properties of the Berezinskii-KosterlitzThouless (BKT) transition, associated with a sizable amplification of the phase stiffness with respect to nodeless-gap superconductors. The enhanced stiffness originates from extended regions of vanishing gap around the nodal lines of the Brillouin zone (BZ). Our study, based on mean-field and BKT theory, presents a comparative analysis of s-wave and d-wave scenarios, highlighting the features of the latter that boost the stiffness and the BKT transition temperature (TBKT). The comparison centers on two quantities: the mean-field critical temperature and the maximum superconducting gap related to the pairing strengths. We present a phase diagram that captures the scaling of TBKT with respect to the mean-field critical temperature across the BCS–BE crossover and the evolution
of the pseudogap. The zero-temperature phase stiffness intensity map over the BZ is also presented, with a distinctly two-component structure consisting of low- and high-stiffness regions, whose extent depends on microscopic system parameters. These results identify the nodal gap structure of strongly coupled 2D superconductors as a likely enabler for enhanced stiffness and TBKT compared
to their s-wave counterparts.},
keywords = {},
pubstate = {published},
tppubtype = {misc}
}

Fechar
We reveal the key role of the d-wave symmetry of the superconducting gap in strongly coupled two-dimensional (2D) superconductors in determining the properties of the Berezinskii-KosterlitzThouless (BKT) transition, associated with a sizable amplification of the phase stiffness with respect to nodeless-gap superconductors. The enhanced stiffness originates from extended regions of vanishing gap around the nodal lines of the Brillouin zone (BZ). Our study, based on mean-field and BKT theory, presents a comparative analysis of s-wave and d-wave scenarios, highlighting the features of the latter that boost the stiffness and the BKT transition temperature (TBKT). The comparison centers on two quantities: the mean-field critical temperature and the maximum superconducting gap related to the pairing strengths. We present a phase diagram that captures the scaling of TBKT with respect to the mean-field critical temperature across the BCS–BE crossover and the evolution
of the pseudogap. The zero-temperature phase stiffness intensity map over the BZ is also presented, with a distinctly two-component structure consisting of low- and high-stiffness regions, whose extent depends on microscopic system parameters. These results identify the nodal gap structure of strongly coupled 2D superconductors as a likely enabler for enhanced stiffness and TBKT compared
to their s-wave counterparts.
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https://arxiv.org/abs/2511.16385
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5.
Carvalho, Gabriel L.; Piero, João V. B. Del; Silva, Flávia C. Assis; Amorim, Rodrigo G.; Freitas, Jair C. C.; Scopel, Wanderlã L.
Functionalized graphene sensors for detecting coffee-related compounds Journal Article
Em: Applied Surface Science, 2025, ISSN: 0169-4332.
Resumo | Links | BibTeX | Tags:
@article{Carvalho2025,
title = {Functionalized graphene sensors for detecting coffee-related compounds},
author = {Gabriel L. Carvalho and João V.B. Del Piero and Flávia C. Assis Silva and Rodrigo G. Amorim and Jair C.C. Freitas and Wanderlã L. Scopel},
doi = {10.1016/j.apsusc.2025.163739},
issn = {0169-4332},
year = {2025},
date = {2025-11-15},
urldate = {2025-06-00},
journal = {Applied Surface Science},
publisher = {Elsevier BV},
abstract = {Coffee is a globally consumed beverage that needs high quality and production standards. Consequently, concerns regarding its quality are widespread, making the identification of its chemical components and of potential substances resulting from the cultivation process highly desirable. In this work, theoretical calculations based on the density functional theory combined with non-equilibrium Green’s function were employed to assess the potential of graphene-based devices for molecular detection and sensing. The quantum calculations were used to investigate the interaction between graphene-based systems (including pristine graphene and oxygen-containing graphene sheets) and individual molecules such as caffeine, trigonelline, and glyphosate. The binding energy analysis revealed that epoxy- and hydroxyl-functionalized graphene sheets exhibit a stronger interaction with the target molecules in comparison with pristine graphene. The transmission curve obtained for each molecule allowed the identification of individual molecules on the devices based on conductance changes. Since reduced graphene oxide (rGO) is known to contain a distribution of oxygen functional groups (such as epoxy and hydroxyl groups) surrounded by large regions of interconnected hexagonal rings of sp-hybridized carbon atoms, the obtained results indicate then that different types of target molecules can be detected using an rGO-based device. This underscores the capability of carbon-based materials to exhibit remarkable sensitivity and selectivity in the detection of organic molecules, which are of special interest for molecular sensing applications in general and for the coffee production sector in particular.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}

Fechar
Coffee is a globally consumed beverage that needs high quality and production standards. Consequently, concerns regarding its quality are widespread, making the identification of its chemical components and of potential substances resulting from the cultivation process highly desirable. In this work, theoretical calculations based on the density functional theory combined with non-equilibrium Green’s function were employed to assess the potential of graphene-based devices for molecular detection and sensing. The quantum calculations were used to investigate the interaction between graphene-based systems (including pristine graphene and oxygen-containing graphene sheets) and individual molecules such as caffeine, trigonelline, and glyphosate. The binding energy analysis revealed that epoxy- and hydroxyl-functionalized graphene sheets exhibit a stronger interaction with the target molecules in comparison with pristine graphene. The transmission curve obtained for each molecule allowed the identification of individual molecules on the devices based on conductance changes. Since reduced graphene oxide (rGO) is known to contain a distribution of oxygen functional groups (such as epoxy and hydroxyl groups) surrounded by large regions of interconnected hexagonal rings of sp-hybridized carbon atoms, the obtained results indicate then that different types of target molecules can be detected using an rGO-based device. This underscores the capability of carbon-based materials to exhibit remarkable sensitivity and selectivity in the detection of organic molecules, which are of special interest for molecular sensing applications in general and for the coffee production sector in particular.
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doi:10.1016/j.apsusc.2025.163739
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6.
Piero, João V B Del; Miwa, Roberto H.; Scopel, Wanderlã L.
Vanadium incorporation in 2D-layered MoSe2 Journal Article
Em: J. Phys.: Condens. Matter, vol. 37, não 4, 2025, ISSN: 1361-648X.
Resumo | Links | BibTeX | Tags:
@article{DelPiero2024,
title = {Vanadium incorporation in 2D-layered MoSe2},
author = {João V B Del Piero and Roberto H. Miwa and Wanderlã L. Scopel},
url = {https://iopscience.iop.org/article/10.1088/1361-648X/ad8abb/meta},
doi = {10.1088/1361-648x/ad8abb},
issn = {1361-648X},
year = {2025},
date = {2025-11-11},
urldate = {2025-01-27},
journal = {J. Phys.: Condens. Matter},
volume = {37},
number = {4},
publisher = {IOP Publishing},
abstract = {Recent advances in experimental techniques have made it possible to manipulate the structural and electronic properties of two-dimensional layered materials (2DM) through interaction with foreign atoms. Using quantum mechanics calculations based on the density functional theory, we explored the dependency of the structural, energetic, electronic, and magnetic properties of the interaction between Vanadium (V) atoms and monolayer and bilayer MoSe2. Spin-polarized metallic behavior was observed for high V concentration, and a semiconductor/metal interface emerged due to V adsorption on top of BL MoSe2. Our research demonstrated that the functionalization of 2D materials makes an important contribution to the design of spintronic devices based on a 2D-layered materials platform.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}

Fechar
Recent advances in experimental techniques have made it possible to manipulate the structural and electronic properties of two-dimensional layered materials (2DM) through interaction with foreign atoms. Using quantum mechanics calculations based on the density functional theory, we explored the dependency of the structural, energetic, electronic, and magnetic properties of the interaction between Vanadium (V) atoms and monolayer and bilayer MoSe2. Spin-polarized metallic behavior was observed for high V concentration, and a semiconductor/metal interface emerged due to V adsorption on top of BL MoSe2. Our research demonstrated that the functionalization of 2D materials makes an important contribution to the design of spintronic devices based on a 2D-layered materials platform.
Fechar
https://iopscience.iop.org/article/10.1088/1361-648X/ad8abb/meta
doi:10.1088/1361-648x/ad8abb
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7.
Zanineli, Pedro H. M.; Monteiro, Matheus Zaia; Wasques, Vinicius Francisco; Simões, Francielle Santo Pedro; Schleder, Gabriel R.
Fuzzy Neural Network Performance and Interpretability of Quantum Wavefunction Probability Predictions Miscellaneous
2025.
Resumo | Links | BibTeX | Tags:
@misc{zanineli2025fuzzyneuralnetworkperformance,
title = {Fuzzy Neural Network Performance and Interpretability of Quantum Wavefunction Probability Predictions},
author = {Pedro H. M. Zanineli and Matheus Zaia Monteiro and Vinicius Francisco Wasques and Francielle Santo Pedro Simões and Gabriel R. Schleder},
url = {https://arxiv.org/abs/2511.05261},
year = {2025},
date = {2025-11-07},
urldate = {2025-01-01},
abstract = {Predicting quantum wavefunction probability distributions is crucial for computational chemistry and materials science, yet machine learning (ML) models often face a trade-off between accuracy and interpretability. This study compares Artificial Neural Networks (ANNs) and Adaptive Neuro-Fuzzy Inference Systems (ANFIS) in modeling quantum probability distributions for the H ion, leveraging data generated via Physics-Informed Neural Networks (PINNs). While ANN achieved superior accuracy (R = 0.99 vs ANFIS's 0.95 with Gaussian membership functions), it required over 50x more parameters (2,305 vs 39-45). ANFIS, however, provided unique interpretability: its Gaussian membership functions encoded spatial electron localization near proton positions (), mirroring Born probability densities, while fuzzy rules reflected quantum superposition principles. Rules prioritizing the internuclear direction revealed the system's 1D symmetry, aligning with Linear Combination of Atomic Orbitals theory--a novel data-driven perspective on orbital hybridization. Membership function variances () further quantified electron delocalization trends, and peak prediction errors highlighted unresolved quantum cusps. The choice of functions critically impacted performance: Gaussian/Generalized Bell outperformed Sigmoid, with errors improving as training data increased, showing scalability. This study underscores the context-dependent value of ML: ANN for precision and ANFIS for interpretable, parameter-efficient approximations that link inputs to physical behavior. These findings advocate hybrid approaches in quantum simulations, balancing accuracy with explainability to accelerate discovery. Future work should extend ANFIS to multi-electron systems and integrate domain-specific constraints (e.g., kinetic energy terms), bridging data-driven models and fundamental physics.},
keywords = {},
pubstate = {published},
tppubtype = {misc}
}

Fechar
Predicting quantum wavefunction probability distributions is crucial for computational chemistry and materials science, yet machine learning (ML) models often face a trade-off between accuracy and interpretability. This study compares Artificial Neural Networks (ANNs) and Adaptive Neuro-Fuzzy Inference Systems (ANFIS) in modeling quantum probability distributions for the H ion, leveraging data generated via Physics-Informed Neural Networks (PINNs). While ANN achieved superior accuracy (R = 0.99 vs ANFIS's 0.95 with Gaussian membership functions), it required over 50x more parameters (2,305 vs 39-45). ANFIS, however, provided unique interpretability: its Gaussian membership functions encoded spatial electron localization near proton positions (), mirroring Born probability densities, while fuzzy rules reflected quantum superposition principles. Rules prioritizing the internuclear direction revealed the system's 1D symmetry, aligning with Linear Combination of Atomic Orbitals theory–a novel data-driven perspective on orbital hybridization. Membership function variances () further quantified electron delocalization trends, and peak prediction errors highlighted unresolved quantum cusps. The choice of functions critically impacted performance: Gaussian/Generalized Bell outperformed Sigmoid, with errors improving as training data increased, showing scalability. This study underscores the context-dependent value of ML: ANN for precision and ANFIS for interpretable, parameter-efficient approximations that link inputs to physical behavior. These findings advocate hybrid approaches in quantum simulations, balancing accuracy with explainability to accelerate discovery. Future work should extend ANFIS to multi-electron systems and integrate domain-specific constraints (e.g., kinetic energy terms), bridging data-driven models and fundamental physics.
Fechar
https://arxiv.org/abs/2511.05261
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8.
Rivera, D.; Sabino, Fernando P.; Raebiger, H.; Ruzsinszky, A.; Perdew, J. P.; Dalpian, G. M.
Exchange field induced symmetry breaking in quantum hexaborides Miscellaneous
2025.
Resumo | Links | BibTeX | Tags:
@misc{rivera2025exchangefieldinducedsymmetry,
title = {Exchange field induced symmetry breaking in quantum hexaborides},
author = {D. Rivera and Fernando P. Sabino and H. Raebiger and A. Ruzsinszky and J. P. Perdew and G. M. Dalpian},
url = {https://arxiv.org/abs/2511.05738},
year = {2025},
date = {2025-11-07},
urldate = {2025-01-01},
abstract = {Symmetry breaking (SB) has proven to be a powerful approach for describing quantum materials: strong correlation, mass renormalization, and complex phase transitions are among the phenomena that SB can capture, even when coupled to a mean-field-like theory. Traditionally, corrective schemes were required to account for these effects; however, SB has emerged as an alternative that can also successfully describe the intricate physics of quantum materials. Here, we explore spin SB on EuB6 and SmB6 and how its relation to the exchange field can determine onsite properties, depending on the type of symmetry breaking. Using spin-polarized Density Functional Theory (DFT) calculations with the r2SCAN functional, we systematically compare four magnetic configurations, one totally symmetric - non-magnetic (NM) configuration - and three with different types of symmetry breaking: ferromagnetic (FM), antiferromagnetic (AFM) and a paramagnetic (PM) configuration - modeled through a Special Quasirandom Structure (SQS) method - to capture local symmetry-breaking effects. Our results show that the PM configuration produces distinct magnetic environments for the rare-earth atoms, leading to different exchange fields. These, in turn, induce symmetry breaking in the electronic and magnetic properties of Eu and Sm. Those results provide an alternative explanation for the experimental results on both materials, EuB6 and SmB6, where X-ray Absorption Spectroscopy (XAS) and X-ray Absorption Near Edge Structure (XANES) measurements suggest the presence of multiple atomic environments, previously attributed to a mixed-valence configuration.},
keywords = {},
pubstate = {published},
tppubtype = {misc}
}

Fechar
Symmetry breaking (SB) has proven to be a powerful approach for describing quantum materials: strong correlation, mass renormalization, and complex phase transitions are among the phenomena that SB can capture, even when coupled to a mean-field-like theory. Traditionally, corrective schemes were required to account for these effects; however, SB has emerged as an alternative that can also successfully describe the intricate physics of quantum materials. Here, we explore spin SB on EuB6 and SmB6 and how its relation to the exchange field can determine onsite properties, depending on the type of symmetry breaking. Using spin-polarized Density Functional Theory (DFT) calculations with the r2SCAN functional, we systematically compare four magnetic configurations, one totally symmetric – non-magnetic (NM) configuration – and three with different types of symmetry breaking: ferromagnetic (FM), antiferromagnetic (AFM) and a paramagnetic (PM) configuration – modeled through a Special Quasirandom Structure (SQS) method – to capture local symmetry-breaking effects. Our results show that the PM configuration produces distinct magnetic environments for the rare-earth atoms, leading to different exchange fields. These, in turn, induce symmetry breaking in the electronic and magnetic properties of Eu and Sm. Those results provide an alternative explanation for the experimental results on both materials, EuB6 and SmB6, where X-ray Absorption Spectroscopy (XAS) and X-ray Absorption Near Edge Structure (XANES) measurements suggest the presence of multiple atomic environments, previously attributed to a mixed-valence configuration.
Fechar
https://arxiv.org/abs/2511.05738
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9.
Mendonça, Bruno H. S.; Moraes, Elizane E.; Abal, João P. K.; Valle, João V. L.; Fonseca, Tássylla O.; Chacham, Hélio
Influence of carbon nanocone structure on ultra-efficient water flow Miscellaneous
2025.
Resumo | Links | BibTeX | Tags:
@misc{mendonça2025influencecarbonnanoconestructure,
title = {Influence of carbon nanocone structure on ultra-efficient water flow},
author = {Bruno H. S. Mendonça and Elizane E. Moraes and João P. K. Abal and João V. L. Valle and Tássylla O. Fonseca and Hélio Chacham},
url = {https://arxiv.org/abs/2511.04701},
year = {2025},
date = {2025-11-01},
urldate = {2025-01-01},
abstract = {In this study, using nonequilibrium molecular dynamics simulation, the water flow in carbon nanocones is studied using the TIP4P/2005 rigid water model. The results demonstrate a nonuniform dependence of the flow on the cone apex angle and the diameter of the opening where the flow is established, leading to a significant increase in the flow in some cases. The effects of cone diameter and pressure gradient are investigated to explain flow behavior with different system structures. We observed that some cones can optimize the water flow precisely. Nanocones with a larger opening facilitate the sliding of water, significantly increasing the flow, thus being promising membranes for technological use in water impurity separation processes. Nanocones with narrower opening angles limited water mobility due to excessive confinement. This phenomenon is linked to the ability of water to form a larger hydrogen-bond network in typical systems with diameters of this size, obtaining a single-layer water structure. Nanocones act as selective nanofilters capable of allowing water molecules to pass through while blocking salts and impurities. The conical shape of their structures creates a directed flow that improves separation efficiency. Membranes based on carbon nanocones are becoming promising for clean, smart, and efficient technologies. The combination of transport speed, selectivity, and structural control put them ahead of other nanostructures for various purposes.},
keywords = {},
pubstate = {published},
tppubtype = {misc}
}

Fechar
In this study, using nonequilibrium molecular dynamics simulation, the water flow in carbon nanocones is studied using the TIP4P/2005 rigid water model. The results demonstrate a nonuniform dependence of the flow on the cone apex angle and the diameter of the opening where the flow is established, leading to a significant increase in the flow in some cases. The effects of cone diameter and pressure gradient are investigated to explain flow behavior with different system structures. We observed that some cones can optimize the water flow precisely. Nanocones with a larger opening facilitate the sliding of water, significantly increasing the flow, thus being promising membranes for technological use in water impurity separation processes. Nanocones with narrower opening angles limited water mobility due to excessive confinement. This phenomenon is linked to the ability of water to form a larger hydrogen-bond network in typical systems with diameters of this size, obtaining a single-layer water structure. Nanocones act as selective nanofilters capable of allowing water molecules to pass through while blocking salts and impurities. The conical shape of their structures creates a directed flow that improves separation efficiency. Membranes based on carbon nanocones are becoming promising for clean, smart, and efficient technologies. The combination of transport speed, selectivity, and structural control put them ahead of other nanostructures for various purposes.
Fechar
https://arxiv.org/abs/2511.04701
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10.
Barbosa, Cybelle C. C. M.; Ramos, Barbara L.; Ferreira, Elivelton A.; Amorim, Rodrigo G.; da Silva, Ramon S.; Noce, Rodrigo Della; de Carvalho, Adriana E.; de Pietre, Mendelssolm K.
Synergistic Experimental and Theoretical Studies on Pesticide Detection in River samples Using Faujasite-CTAB Modified Carbon Paste Electrode Journal Article
Em: Water Air Soil Pollut, vol. 237, não 2, 2025, ISSN: 1573-2932.
Resumo | Links | BibTeX | Tags:
@article{Barbosa2025,
title = {Synergistic Experimental and Theoretical Studies on Pesticide Detection in River samples Using Faujasite-CTAB Modified Carbon Paste Electrode},
author = {Cybelle C. C. M. Barbosa and Barbara L. Ramos and Elivelton A. Ferreira and Rodrigo G. Amorim and Ramon S. da Silva and Rodrigo Della Noce and Adriana E. de Carvalho and Mendelssolm K. de Pietre},
doi = {10.1007/s11270-025-08787-1},
issn = {1573-2932},
year = {2025},
date = {2025-11-01},
urldate = {2026-01-00},
journal = {Water Air Soil Pollut},
volume = {237},
number = {2},
publisher = {Springer Science and Business Media LLC},
abstract = {This study presents the development and electroanalytical application of a low-cost, sensitive, and environmentally friendly voltammetric sensor for the detection of carbendazim (CBZ) in surface water samples. The sensor is based on carbon paste electrode (CPE) modified with faujasite zeolites (Fau) and faujasite functionalized with CTAB (Fau-CTAB). The insertion of zeolites as a modifier increases the effective area of the electrodes, raising the sensitivity of the system. The precision of the developed method shows satisfactory repeatability and reproducibility with respect to the obtained results. The analytical curve exhibits two linear regions, where the calculated detection and quantification limits are 0.0124 µmol L−1 and 0. 0377 µmol L−1, respectively. In this sense, the proposed sensor is successfully applied to determine traces of CBZ in surface water samples from the Paraiba do Sul River, achieving recovery values ranging from 98.91 to 103.61%. Additionally, a theoretical model based on density functional theory (DFT) calculations is proposed to evaluate the interactions between CTAB and CBZ. This model provides theoretical insights that align with experimental observations, offering a clearer physical understanding of these interactions.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}

Fechar
This study presents the development and electroanalytical application of a low-cost, sensitive, and environmentally friendly voltammetric sensor for the detection of carbendazim (CBZ) in surface water samples. The sensor is based on carbon paste electrode (CPE) modified with faujasite zeolites (Fau) and faujasite functionalized with CTAB (Fau-CTAB). The insertion of zeolites as a modifier increases the effective area of the electrodes, raising the sensitivity of the system. The precision of the developed method shows satisfactory repeatability and reproducibility with respect to the obtained results. The analytical curve exhibits two linear regions, where the calculated detection and quantification limits are 0.0124 µmol L−1 and 0. 0377 µmol L−1, respectively. In this sense, the proposed sensor is successfully applied to determine traces of CBZ in surface water samples from the Paraiba do Sul River, achieving recovery values ranging from 98.91 to 103.61%. Additionally, a theoretical model based on density functional theory (DFT) calculations is proposed to evaluate the interactions between CTAB and CBZ. This model provides theoretical insights that align with experimental observations, offering a clearer physical understanding of these interactions.
Fechar
doi:10.1007/s11270-025-08787-1
Fechar
11.
Puccinelli, Thiago; Farigliano, Lucas Martin; Dalpian, Gustavo Martini
Stability and Dynamics of Sn-based Halide Perovskites: Insights from MACE-MP-0 and Molecular Dynamics Simulations Miscellaneous
2025.
Resumo | Links | BibTeX | Tags:
@misc{puccinelli2025stabilitydynamicssnbasedhalide,
title = {Stability and Dynamics of Sn-based Halide Perovskites: Insights from MACE-MP-0 and Molecular Dynamics Simulations},
author = {Thiago Puccinelli and Lucas Martin Farigliano and Gustavo Martini Dalpian},
url = {https://arxiv.org/abs/2510.26998},
year = {2025},
date = {2025-10-30},
urldate = {2025-01-01},
abstract = {Tin-based halide perovskites have emerged as promising lead-free alternatives for optoelectronic applications, yet their structural stability and phase behavior at finite temperatures remain challenging to predict. Here, we assess the predictive capabilities of the foundational machine learning model MACE-MP-0 - trained on a broad chemical space and applied without system-specific fine-tuning - for the temperature-dependent behavior of CsSnBr3 and Cs2SnBr6. Molecular Dynamics simulations in the NpT ensemble were performed from 100 K to 500 K, and thermodynamic and structural descriptors including enthalpy, specific heat, radial distribution functions, translational order, bond angle distributions, and vibrational spectra were analyzed. Our results show that CsSnBr3 undergoes a low-temperature orthorhombic-to-cubic phase transition, evidenced by both the evolution of lattice parameters and subtle anomalies in enthalpy and specific heat, although the experimentally observed intermediate tetragonal phase is not captured. In contrast, Cs2SnBr6 remains cubic and maintains a more rigid octahedral framework across the entire temperature range. Overall, MACE-MP-0 qualitatively reproduces key thermal and structural features of these materials, highlighting its usefulness as a first step for studying new materials. For cases where capturing more subtle phase behavior is required, system-specific fine-tuning with Density Functional Theory data should be considered.},
keywords = {},
pubstate = {published},
tppubtype = {misc}
}

Fechar
Tin-based halide perovskites have emerged as promising lead-free alternatives for optoelectronic applications, yet their structural stability and phase behavior at finite temperatures remain challenging to predict. Here, we assess the predictive capabilities of the foundational machine learning model MACE-MP-0 – trained on a broad chemical space and applied without system-specific fine-tuning – for the temperature-dependent behavior of CsSnBr3 and Cs2SnBr6. Molecular Dynamics simulations in the NpT ensemble were performed from 100 K to 500 K, and thermodynamic and structural descriptors including enthalpy, specific heat, radial distribution functions, translational order, bond angle distributions, and vibrational spectra were analyzed. Our results show that CsSnBr3 undergoes a low-temperature orthorhombic-to-cubic phase transition, evidenced by both the evolution of lattice parameters and subtle anomalies in enthalpy and specific heat, although the experimentally observed intermediate tetragonal phase is not captured. In contrast, Cs2SnBr6 remains cubic and maintains a more rigid octahedral framework across the entire temperature range. Overall, MACE-MP-0 qualitatively reproduces key thermal and structural features of these materials, highlighting its usefulness as a first step for studying new materials. For cases where capturing more subtle phase behavior is required, system-specific fine-tuning with Density Functional Theory data should be considered.
Fechar
https://arxiv.org/abs/2510.26998
Fechar
12.
Spalenza, Pedro Elias Priori; de Souza, Fábio Arthur Leão; Rodrigues, Debora C. M.; Amorim, Rodrigo G.; Villegas, Cesar E. P.; Scopel, Wanderlã L.; Pandey, Ravindra
Reliable Detection of SF6 Breakdown Byproducts Using 2D Non-Hexagonal Carbon Allotrope Nanosheets Journal Article
Em: ACS Appl. Nano Mater., 2025, ISSN: 2574-0970.
Resumo | Links | BibTeX | Tags:
@article{Spalenza2025b,
title = {Reliable Detection of SF6 Breakdown Byproducts Using 2D Non-Hexagonal Carbon Allotrope Nanosheets},
author = {Pedro Elias Priori Spalenza and Fábio Arthur Leão de Souza and Debora C. M. Rodrigues and Rodrigo G. Amorim and Cesar E. P. Villegas and Wanderlã L. Scopel and Ravindra Pandey},
doi = {10.1021/acsanm.5c03937},
issn = {2574-0970},
year = {2025},
date = {2025-10-28},
urldate = {2025-10-28},
journal = {ACS Appl. Nano Mater.},
publisher = {American Chemical Society (ACS)},
abstract = {Sulfur hexafluoride (SF6), widely used as an insulating gas in the power industry, decomposes during long-term operation into byproducts such as H2S, SO2, SO2F2, and SOF2. Reliable detection of these compounds is essential, since their type and concentration provide diagnostic signatures of faults in gas-insulated switchgear. We employ density functional theory combined with nonequilibrium Green’s function calculations to evaluate pristine two-dimensional carbon allotropes with nonhexagonal rings, namely Graphene+, T-graphene, and Biphenylene, as potential field-effect nanosensors. To characterize the surfaces’ atomic structures, we simulated scanning tunneling microscopy images for filled states. Each surface exhibits a distinct brightness pattern that allows its identification. All interactions occur via physisorption, enabling rapid recovery and device reusability. Graphene+ uniquely identifies SO2 and SOF2 at a single gate voltage, while T-graphene and Biphenylene selectively detect H2S and SO2. These findings demonstrate that nonhexagonal carbon nanosheets combine high sensitivity, fast recovery, and intrinsic selectivity, underscoring their potential for real-time monitoring of SF6 degradation products in power systems.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}

Fechar
Sulfur hexafluoride (SF6), widely used as an insulating gas in the power industry, decomposes during long-term operation into byproducts such as H2S, SO2, SO2F2, and SOF2. Reliable detection of these compounds is essential, since their type and concentration provide diagnostic signatures of faults in gas-insulated switchgear. We employ density functional theory combined with nonequilibrium Green’s function calculations to evaluate pristine two-dimensional carbon allotropes with nonhexagonal rings, namely Graphene+, T-graphene, and Biphenylene, as potential field-effect nanosensors. To characterize the surfaces’ atomic structures, we simulated scanning tunneling microscopy images for filled states. Each surface exhibits a distinct brightness pattern that allows its identification. All interactions occur via physisorption, enabling rapid recovery and device reusability. Graphene+ uniquely identifies SO2 and SOF2 at a single gate voltage, while T-graphene and Biphenylene selectively detect H2S and SO2. These findings demonstrate that nonhexagonal carbon nanosheets combine high sensitivity, fast recovery, and intrinsic selectivity, underscoring their potential for real-time monitoring of SF6 degradation products in power systems.
Fechar
doi:10.1021/acsanm.5c03937
Fechar
13.
Nambisan, Ameya; Günzler, Simon; Rieger, Dennis; Gosling, Nicolas; Geisert, Simon; Carpentier, Victor; Zapata, Nicolas; Field, Mitchell; Milošević, Milorad V.; Lopez, Carlos A. Diaz; Padurariu, Ciprian; Kubala, Björn; Ankerhold, Joachim; Wernsdorfer, Wolfgang; Spiecker, Martin; Pop, Ioan M.
Quantum Coherence in Superconducting Vortex States Miscellaneous
2025.
Resumo | Links | BibTeX | Tags:
@misc{nambisan2025quantumcoherencesuperconductingvortex,
title = {Quantum Coherence in Superconducting Vortex States},
author = {Ameya Nambisan and Simon Günzler and Dennis Rieger and Nicolas Gosling and Simon Geisert and Victor Carpentier and Nicolas Zapata and Mitchell Field and Milorad V. Milošević and Carlos A. Diaz Lopez and Ciprian Padurariu and Björn Kubala and Joachim Ankerhold and Wolfgang Wernsdorfer and Martin Spiecker and Ioan M. Pop},
url = {https://arxiv.org/abs/2510.19769},
year = {2025},
date = {2025-10-22},
urldate = {2025-01-01},
abstract = {Abrikosov vortices, where the superconducting gap is completely suppressed in the core, are dissipative, semi-classical entities that impact applications from high-current-density wires to superconducting quantum devices. In contrast, we present evidence that vortices trapped in granular superconducting films can behave as two-level systems, exhibiting microsecond-range quantum coherence and energy relaxation times that reach fractions of a millisecond. These findings support recent theoretical modeling of superconductors with granularity on the scale of the coherence length as tunnel junction networks, resulting in gapped vortices. Using the tools of circuit quantum electrodynamics, we perform coherent manipulation and quantum non-demolition readout of vortex states in granular aluminum microwave resonators, heralding new directions for quantum information processing, materials characterization, and sensing.},
keywords = {},
pubstate = {published},
tppubtype = {misc}
}

Fechar
Abrikosov vortices, where the superconducting gap is completely suppressed in the core, are dissipative, semi-classical entities that impact applications from high-current-density wires to superconducting quantum devices. In contrast, we present evidence that vortices trapped in granular superconducting films can behave as two-level systems, exhibiting microsecond-range quantum coherence and energy relaxation times that reach fractions of a millisecond. These findings support recent theoretical modeling of superconductors with granularity on the scale of the coherence length as tunnel junction networks, resulting in gapped vortices. Using the tools of circuit quantum electrodynamics, we perform coherent manipulation and quantum non-demolition readout of vortex states in granular aluminum microwave resonators, heralding new directions for quantum information processing, materials characterization, and sensing.
Fechar
https://arxiv.org/abs/2510.19769
Fechar
14.
da Silva, Ramon S.; Souza, Ana J. F.; Sangi, Diego P.; Amorim, Rodrigo G.
Dual Pathways, One Framework: Theoretical Insights into the Benzimidazole × Benzodiazepine Crossroads from o -Phenylenediamine and 2-Cyanoacrylate Derivatives Journal Article
Em: ACS Omega, 2025, ISSN: 2470-1343.
Resumo | Links | BibTeX | Tags:
@article{daSilva2025,
title = {Dual Pathways, One Framework: Theoretical Insights into the Benzimidazole × Benzodiazepine Crossroads from \textit{o} -Phenylenediamine and 2-Cyanoacrylate Derivatives},
author = {Ramon S. da Silva and Ana J. F. Souza and Diego P. Sangi and Rodrigo G. Amorim},
doi = {10.1021/acsomega.5c05925},
issn = {2470-1343},
year = {2025},
date = {2025-10-21},
urldate = {2025-10-21},
journal = {ACS Omega},
publisher = {American Chemical Society (ACS)},
abstract = {Ketene dithioacetals represent a significant class of molecules with a pivotal role in organic synthesis, particularly as versatile building blocks for the development of novel pharmaceutical compounds. We employed density functional theory (DFT) calculations in both ethanol and the gas phase to elucidate the specific mechanism of the reaction between methyl 2-cyano-3,3-bis(methylthio)acrylate and o-phenylenediamine. This approach provides a theoretical basis for understanding the system’s behavior and reactivity at the molecular scale. Our study evaluates the competition between two reported products: 4-methylsulfanyl-2-oxo-2,5-dihydro-1H-benzo[b][1,4]diazepine-3-carbonitrile and methyl 2-cyano-2-(1,3-dihydro-2H-benzo[d]imidazole-2-ylidene)acetate. The present findings reveal that both reactions are exothermic, with the formation of methyl 2-cyano-2-(1,3-dihydro-2H-benzo[d]imidazole-2-ylidene)acetate being more thermodynamically favorable. This combination of experimental evidence and computational analysis bridges the gap between synthetic applications and mechanistic understanding, enhancing the design and optimization of organic reactions.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}

Fechar
Ketene dithioacetals represent a significant class of molecules with a pivotal role in organic synthesis, particularly as versatile building blocks for the development of novel pharmaceutical compounds. We employed density functional theory (DFT) calculations in both ethanol and the gas phase to elucidate the specific mechanism of the reaction between methyl 2-cyano-3,3-bis(methylthio)acrylate and o-phenylenediamine. This approach provides a theoretical basis for understanding the system’s behavior and reactivity at the molecular scale. Our study evaluates the competition between two reported products: 4-methylsulfanyl-2-oxo-2,5-dihydro-1H-benzo[b][1,4]diazepine-3-carbonitrile and methyl 2-cyano-2-(1,3-dihydro-2H-benzo[d]imidazole-2-ylidene)acetate. The present findings reveal that both reactions are exothermic, with the formation of methyl 2-cyano-2-(1,3-dihydro-2H-benzo[d]imidazole-2-ylidene)acetate being more thermodynamically favorable. This combination of experimental evidence and computational analysis bridges the gap between synthetic applications and mechanistic understanding, enhancing the design and optimization of organic reactions.
Fechar
doi:10.1021/acsomega.5c05925
Fechar
15.
Shafiei, Mohammad; Fazileh, Farhad; Milošević, Milorad V.
Linearly polarized light enables chiral edge transport in quasi-2D Dirac materials Miscellaneous
2025.
Resumo | Links | BibTeX | Tags:
@misc{shafiei2025linearlypolarizedlightenables,
title = {Linearly polarized light enables chiral edge transport in quasi-2D Dirac materials},
author = {Mohammad Shafiei and Farhad Fazileh and Milorad V. Milošević},
url = {https://arxiv.org/abs/2510.14447},
year = {2025},
date = {2025-10-16},
urldate = {2025-01-01},
abstract = {Floquet engineering with high-frequency light offers dynamic control over topological phases in quantum materials. While in 3D Dirac systems circularly polarized light is known to induce topological phase transitions via gap opening, linearly polarized light (LPL) has generally been considered ineffective. Here we show that in quasi-2D Dirac materials the second-order momentum term arising from the intersurface coupling can induce a topological phase transition under LPL, leading to chiral edge channels. Considering an ultrathin BiSe film as a representative system, we show that this transition occurs at experimentally accessible light intensities. Our results thus promote quasi-2D materials as viable platforms for light-controlled topological phases, expanding the potential of Floquet topological engineering.},
keywords = {},
pubstate = {published},
tppubtype = {misc}
}

Fechar
Floquet engineering with high-frequency light offers dynamic control over topological phases in quantum materials. While in 3D Dirac systems circularly polarized light is known to induce topological phase transitions via gap opening, linearly polarized light (LPL) has generally been considered ineffective. Here we show that in quasi-2D Dirac materials the second-order momentum term arising from the intersurface coupling can induce a topological phase transition under LPL, leading to chiral edge channels. Considering an ultrathin BiSe film as a representative system, we show that this transition occurs at experimentally accessible light intensities. Our results thus promote quasi-2D materials as viable platforms for light-controlled topological phases, expanding the potential of Floquet topological engineering.
Fechar
https://arxiv.org/abs/2510.14447
Fechar
16.
Sabzalipour, Amir; Shafiei, Mohammad; Milošević, Milorad V.
Dissipationless transport by design in ultrathin magnetic topological insulator films Miscellaneous
2025.
Resumo | Links | BibTeX | Tags:
@misc{sabzalipour2025dissipationlesstransportdesignultrathin,
title = {Dissipationless transport by design in ultrathin magnetic topological insulator films},
author = {Amir Sabzalipour and Mohammad Shafiei and Milorad V. Milošević},
url = {https://arxiv.org/abs/2510.12610},
year = {2025},
date = {2025-10-14},
urldate = {2025-01-01},
abstract = {Magnetic topological insulators (MTIs) are among the prominent platforms for the next generation of high-speed and low-power spintronic devices. However, unlike their non-magnetic counterparts, where the surface spin-momentum locking prevents electrons from being scattered by non-magnetic impurities and results in a dissipationless electronic flow, magnetic impurities in MTIs cause dissipation by exerting magnetic torque on the electron spin. Decreasing this resistance is desired to reduce energy consumption and optimize performance of MTIs in envisaged applications. Here we reveal how electronic backscattering can be suppressed in a MTI thin film by external magnetic and/or electronic stimuli, to yield an entirely dissipationless spin-polarized charge transport. Our findings thus present an effective route to preserve spin coherence and enhance spin-current functionality in magnetic topological materials, suggesting design strategies for magneto-electronic and spintronic
devices with strongly reduced energy consumption.
},
keywords = {},
pubstate = {published},
tppubtype = {misc}
}

Fechar
Magnetic topological insulators (MTIs) are among the prominent platforms for the next generation of high-speed and low-power spintronic devices. However, unlike their non-magnetic counterparts, where the surface spin-momentum locking prevents electrons from being scattered by non-magnetic impurities and results in a dissipationless electronic flow, magnetic impurities in MTIs cause dissipation by exerting magnetic torque on the electron spin. Decreasing this resistance is desired to reduce energy consumption and optimize performance of MTIs in envisaged applications. Here we reveal how electronic backscattering can be suppressed in a MTI thin film by external magnetic and/or electronic stimuli, to yield an entirely dissipationless spin-polarized charge transport. Our findings thus present an effective route to preserve spin coherence and enhance spin-current functionality in magnetic topological materials, suggesting design strategies for magneto-electronic and spintronic
devices with strongly reduced energy consumption.

Fechar
https://arxiv.org/abs/2510.12610
Fechar
17.
de Oliveira, P. R. A.; Coelho, I.; Felix, G.; Venezuela, P.; Stavale, F.
Growth and Surface Characterization of a Type-II ZnO/ZnS Heterostructure Journal Article
Em: J. Phys. Chem. C, 2025, ISSN: 1932-7455.
Resumo | Links | BibTeX | Tags:
@article{deOliveira2025,
title = {Growth and Surface Characterization of a Type-II ZnO/ZnS Heterostructure},
author = {P. R. A. de Oliveira and I. Coelho and G. Felix and P. Venezuela and F. Stavale},
doi = {10.1021/acs.jpcc.5c05124},
issn = {1932-7455},
year = {2025},
date = {2025-10-09},
urldate = {2025-10-09},
journal = {J. Phys. Chem. C},
publisher = {American Chemical Society (ACS)},
abstract = {We report the in situ formation of a type-II ZnO/ZnS heterostructure via the thermal oxidation of a ZnS(001) single crystal under a clean controlled oxygen atmosphere. By combining X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM), we investigated the chemical composition, electronic structure, and surface morphology of the resulting interface. Core-level shifts observed in our XPS measurements suggest an upward band-bending due to the formation of a hybrid interface. AFM measurements show that ZnO grows through a layer-plus-island mode, forming distorted hexagonal nanoislands. Our band alignment analysis confirms the type-II heterostructure arrangement with suitable electronic band-edge positions for efficient charge separation, highlighting its potential as a platform for photocatalytic applications, such as hydrogen and oxygen evolution reactions (HER and OER).},
keywords = {},
pubstate = {published},
tppubtype = {article}
}

Fechar
We report the in situ formation of a type-II ZnO/ZnS heterostructure via the thermal oxidation of a ZnS(001) single crystal under a clean controlled oxygen atmosphere. By combining X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM), we investigated the chemical composition, electronic structure, and surface morphology of the resulting interface. Core-level shifts observed in our XPS measurements suggest an upward band-bending due to the formation of a hybrid interface. AFM measurements show that ZnO grows through a layer-plus-island mode, forming distorted hexagonal nanoislands. Our band alignment analysis confirms the type-II heterostructure arrangement with suitable electronic band-edge positions for efficient charge separation, highlighting its potential as a platform for photocatalytic applications, such as hydrogen and oxygen evolution reactions (HER and OER).
Fechar
doi:10.1021/acs.jpcc.5c05124
Fechar
18.
Chattopadhyay, Shreyasi; de Oliveira, Caique Campos; Bhar, Rajarshi; Banik, Dhiman; Pieshkov, Tymofii S.; Puthirath, Anand B.; Pramanik, Atin; Sreeram, P R; Saju, Sreehari K; Costin, Gelu; Vajtai, Robert; Dubey, Brajesh K; Biswas, Krishanu; da Silva Autreto, Pedro Alves; Tiwary, Chandra Sekhar; Ajayan, Pulickel M.
Exploring Sustainable Hydrogen Production from Alkaline Fresh and Seawater Using Natural Ore Derived 2D Bi₂S₃ Journal Article
Em: Small, 2025, ISSN: 1613-6829.
Resumo | Links | BibTeX | Tags:
@article{Chattopadhyay2025,
title = {Exploring Sustainable Hydrogen Production from Alkaline Fresh and Seawater Using Natural Ore Derived 2D Bi_{2}S_{3}},
author = {Shreyasi Chattopadhyay and Caique Campos de Oliveira and Rajarshi Bhar and Dhiman Banik and Tymofii S. Pieshkov and Anand B. Puthirath and Atin Pramanik and P R Sreeram and Sreehari K Saju and Gelu Costin and Robert Vajtai and Brajesh K Dubey and Krishanu Biswas and Pedro Alves da Silva Autreto and Chandra Sekhar Tiwary and Pulickel M. Ajayan},
doi = {10.1002/smll.202509283},
issn = {1613-6829},
year = {2025},
date = {2025-10-07},
urldate = {2025-10-07},
journal = {Small},
publisher = {Wiley},
abstract = {AbstractWater electrolysis for hydrogen, though widely studied, presents exciting opportunities for improvement beyond conventional energy and cost‐intensive catalysts. Natural ores, being abundant and readily available, hold immense promise as sustainable sources of alternative energy materials. Here, this method offers a simple and low‐cost route, not only to make 2D materials but also to develop electrocatalysts from earth‐abundant ores. Synthesis of 2D Bi2S3 is demonstrated via Liquid phase exfoliation (LPE) of the naturally abundant bismuthinite ore. Sustainability of such 2D Bi2S3 is explored for hydrogen evolution reaction (HER) from alkaline fresh and simulated seawater. The exfoliated Bi2S3 exhibits an overpotential of 693 and 678 mV at 10 mA cm‐2 in alkaline fresh and simulated seawater with a durability up to 40 h. From Density Functional Theory (DFT) based First‐principles calculations, sulfur sites are found to bind H‐intermediates strongly in comparison with bismuth sites. Sustainability is further investigated by life cycle calculation. A lower carbon footprint of the 2D Bi2S3 catalyst is observed under both alkaline fresh (21.13 kg CO2eq kg−1 H2) and simulated seawater (15.56 kg CO2eq kg−1 H2). This work extends a sustainable strategy to utilize earth‐abundant natural source for fabricating efficient and durable HER electrocatalysts for future fuel.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}

Fechar
AbstractWater electrolysis for hydrogen, though widely studied, presents exciting opportunities for improvement beyond conventional energy and cost‐intensive catalysts. Natural ores, being abundant and readily available, hold immense promise as sustainable sources of alternative energy materials. Here, this method offers a simple and low‐cost route, not only to make 2D materials but also to develop electrocatalysts from earth‐abundant ores. Synthesis of 2D Bi2S3 is demonstrated via Liquid phase exfoliation (LPE) of the naturally abundant bismuthinite ore. Sustainability of such 2D Bi2S3 is explored for hydrogen evolution reaction (HER) from alkaline fresh and simulated seawater. The exfoliated Bi2S3 exhibits an overpotential of 693 and 678 mV at 10 mA cm‐2 in alkaline fresh and simulated seawater with a durability up to 40 h. From Density Functional Theory (DFT) based First‐principles calculations, sulfur sites are found to bind H‐intermediates strongly in comparison with bismuth sites. Sustainability is further investigated by life cycle calculation. A lower carbon footprint of the 2D Bi2S3 catalyst is observed under both alkaline fresh (21.13 kg CO2eq kg−1 H2) and simulated seawater (15.56 kg CO2eq kg−1 H2). This work extends a sustainable strategy to utilize earth‐abundant natural source for fabricating efficient and durable HER electrocatalysts for future fuel.
Fechar
doi:10.1002/smll.202509283
Fechar
19.
Hasimoto, Leonardo H.; das Neves, Matheus F. F.; Perfecto, Tarcisio M.; Bettini, Jefferson; Leite, Edson R.; Capaz, Rodrigo B.; Santhiago, Murilo
Unraveling the Defects Introduced on the Basal Plane of MoS₂ Monolayers by H₂O₂ for the Hydrogen Evolution Reaction Journal Article
Em: ACS Appl. Energy Mater., 2025, ISSN: 2574-0962.
Resumo | Links | BibTeX | Tags:
@article{Hasimoto2025,
title = {Unraveling the Defects Introduced on the Basal Plane of MoS_{2} Monolayers by H_{2}O_{2} for the Hydrogen Evolution Reaction},
author = {Leonardo H. Hasimoto and Matheus F. F. das Neves and Tarcisio M. Perfecto and Jefferson Bettini and Edson R. Leite and Rodrigo B. Capaz and Murilo Santhiago},
doi = {10.1021/acsaem.5c02263},
issn = {2574-0962},
year = {2025},
date = {2025-10-03},
urldate = {2025-10-03},
journal = {ACS Appl. Energy Mater.},
publisher = {American Chemical Society (ACS)},
abstract = {The introduction of defects is crucial for tuning the electrocatalytic activity of MoS2 monolayers on the basal plane toward the hydrogen evolution reaction (HER). Hydrogen peroxide is a mild, metal-free, and carbon-free oxidant that can activate the basal plane to enhance the HER activity. Depending on the experimental conditions, H2O2 can lead to the formation of edge-like defects and vacancies on the basal plane. In this work, we demonstrate for the first time that exposure to H2O2 solution induces both local strain and sulfur vacancy on MoS2 monolayers. Using high-resolution transmission electron microscopy, we tracked the same sample to understand the significant effects of H2O2 on free-standing MoS2 monolayers at both nanoscale and atomic resolutions. We measured the electrocatalytic activity of the monolayers without introducing unintentional defects associated with the microfabrication process. Our findings revealed an anodic shift in the overpotential required to drive the HER. Thus, our work provides a fundamental basis for understanding the chemical transformations of MoS2 monolayers following the defect engineering step.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}

Fechar
The introduction of defects is crucial for tuning the electrocatalytic activity of MoS2 monolayers on the basal plane toward the hydrogen evolution reaction (HER). Hydrogen peroxide is a mild, metal-free, and carbon-free oxidant that can activate the basal plane to enhance the HER activity. Depending on the experimental conditions, H2O2 can lead to the formation of edge-like defects and vacancies on the basal plane. In this work, we demonstrate for the first time that exposure to H2O2 solution induces both local strain and sulfur vacancy on MoS2 monolayers. Using high-resolution transmission electron microscopy, we tracked the same sample to understand the significant effects of H2O2 on free-standing MoS2 monolayers at both nanoscale and atomic resolutions. We measured the electrocatalytic activity of the monolayers without introducing unintentional defects associated with the microfabrication process. Our findings revealed an anodic shift in the overpotential required to drive the HER. Thus, our work provides a fundamental basis for understanding the chemical transformations of MoS2 monolayers following the defect engineering step.
Fechar
doi:10.1021/acsaem.5c02263
Fechar
20.
Rao, B. Keshav; Rodrigues, Debora C. M.; Scopel, Wanderlã L.; Amorim, Rodrigo G.; Pandey, Ravindra
NO<mml:math xmlns:mml= Journal Article
Em: Diamond and Related Materials, vol. 158, 2025, ISSN: 0925-9635.
Resumo | Links | BibTeX | Tags:
@article{Rao2025,
title = {NO author = {B. Keshav Rao and Debora C.M. Rodrigues and Wanderlã L. Scopel and Rodrigo G. Amorim and Ravindra Pandey},
doi = {10.1016/j.diamond.2025.112672},
issn = {0925-9635},
year = {2025},
date = {2025-10-00},
urldate = {2025-10-00},
journal = {Diamond and Related Materials},
volume = {158},
publisher = {Elsevier BV},
abstract = {Rapid industrialization has led to environmental conditions that necessitate the design and development of advanced sensing devices capable of detecting gases at minute concentrations. In this paper, we present the design of a graphene-based device incorporating an extended 5-5-8 line defect along with nitrogen as a dopant in the lattice. Its structural, electronic, and transport properties of N-doped defective graphene and the adsorbed configuration with gas molecules, including CO, CO, NO, NH, and NO are investigated based on density functional theory. The results indicate that energetically stable N-doped defective graphene is semi-metallic and exhibits n-type doping characteristics. It interacts strongly with NO and NO compared to CO, CO, and NH molecules. Electron transport calculations using the non-equilibrium Green’s Function method for N-doped system reveal the presence of an additional transmission channel at the Fermi level in comparison with a bare one, which significantly diminishes upon adsorption of NO/NO gases. Furthermore, NO and NO gases desorb more rapidly under UV radiation at room temperature. These results suggest that N-doped defective graphene can be a candidate nanomaterial for sensing NO and NO gas molecules.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}

Fechar
Rapid industrialization has led to environmental conditions that necessitate the design and development of advanced sensing devices capable of detecting gases at minute concentrations. In this paper, we present the design of a graphene-based device incorporating an extended 5-5-8 line defect along with nitrogen as a dopant in the lattice. Its structural, electronic, and transport properties of N-doped defective graphene and the adsorbed configuration with gas molecules, including CO, CO, NO, NH, and NO are investigated based on density functional theory. The results indicate that energetically stable N-doped defective graphene is semi-metallic and exhibits n-type doping characteristics. It interacts strongly with NO and NO compared to CO, CO, and NH molecules. Electron transport calculations using the non-equilibrium Green’s Function method for N-doped system reveal the presence of an additional transmission channel at the Fermi level in comparison with a bare one, which significantly diminishes upon adsorption of NO/NO gases. Furthermore, NO and NO gases desorb more rapidly under UV radiation at room temperature. These results suggest that N-doped defective graphene can be a candidate nanomaterial for sensing NO and NO gas molecules.
Fechar
doi:10.1016/j.diamond.2025.112672
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