Dr Fernando Salazar Posadas

@article{energystore2023b,

title = {DFT insights into Cu-driven tuning of chemisorption and physisorption in the hydrogen storage by SnC monolayers},

author = {R. Bermeo-Campos and L. G. Arellano and \'{A}. Miranda and F. Salazar and A. Trejo and R. Oviedo-Roa and M. Cruz-Irisson},

year  = {2023},

date = {2023-09-13},

urldate = {2023-09-13},

journal = {Journal of Energy Storage},

volume = {En revisi\'{o}n},

keywords = {2D monolayers, Density functional calculations},

pubstate = {published},

tppubtype = {article}

}

@article{Jim\'{e}nez-S\'{a}nchez_Morales-Vergara_Salazar_Miranda_Trejo_Hern\'{a}ndez-Hern\'{a}ndez_P\'{e}rez_Cruz-Irisson_2023,

title = {Theoretical study of [111]-germanium nanowires as anode materials in rechargeable batteries: a density functional theory approach},

author = {Ricardo Jim\'{e}nez-S\'{a}nchez and Pedro Morales-Vergara and Fernando Salazar and Alvaro Miranda and Alejandro Trejo and Ivonne J. Hern\'{a}ndez-Hern\'{a}ndez and Luis Antonio P\'{e}rez and Miguel Cruz-Irisson},

url = {https://rmf.smf.mx/ojs/index.php/rmf/article/view/6816},

doi = {10.31349/RevMexFis.69.031604},

year  = {2023},

date = {2023-05-01},

urldate = {2023-05-01},

journal = {Revista Mexicana de F\'{i}sica},

volume = {69},

number = {3 May-Jun},

pages = {031604 1\textendash},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{GONZALEZ2023106840,

title = {Exploring the electronic and mechanical properties of lithium-decorated silicon carbide nanowires for energy storage},

author = {Mario Gonzalez and Fernando Salazar and Alejandro Trejo and \'{A}lvaro Miranda and Roc\'{i}o Nava and Luis Antonio P\'{e}rez and Miguel Cruz-Irisson},

url = {https://www.sciencedirect.com/science/article/pii/S2352152X23002372},

doi = {https://doi.org/10.1016/j.est.2023.106840},

issn = {2352-152X},

year  = {2023},

date = {2023-01-01},

journal = {Journal of Energy Storage},

volume = {62},

pages = {106840},

abstract = {The high chemical stability of silicon carbide (SiC) is attractive to inhibit unwanted side chemical reaction and prolongate the cyclability performance of lithium ion batteries anodes. However, SiC has high surface lithiation energy barrier due to its intrinsic nature and the low electrical conductivity limited the application in this area. The surface modification of SiC is an alternative to boost the lithiation\textendashdelithiation kinetics. Hydrogen incorporation on SiC surface is extensively used in semiconductor industry to passivate electrically active centers. In this work, we present a theoretical study of the effect of surface lithium (Li) atoms on the electronic and mechanical properties of hydrogen passivated SiC nanowires (H-SiCNWs) with zinc-blende structure. The results show that the adsorption of Li on the carbon (C) atoms at the surface of the nanowire introduces new electronic states within the former band gap of the H-SiCNWs, whose main contribution comes from the C and silicon (Si) atoms in the valence and conduction bands, respectively. Moreover, the number of new bands within the former band gap increases as a function of the concentration of Li atoms and the systems remain as intrinsic semiconductors up to the maximum Li concentrations. The formation energy reveals that the stability of the nanowires increases when the concentration of Li atoms augments. Moreover, the values of the open circuit voltage are found between 1.6 and 1.9 V for all studied concentrations of Li atoms and morphologies. The charge population analysis indicates that the Li atoms give up charge to the C ones resulting in ionic bonds. On the other hand, the Young modulus of the H-SiCNWs increases when their diameter augments and their values are lower than that of the bulk SiC. Besides, the Young modulus slightly diminishes when the concentration of Li grows, then the mechanical resistance could offer a large useful life of the electrode. Finally, the maximum theoretical storage capacity values indicate that the SiC nanowires (SiCNWs) are good potential anodic materials for rechargeable Li-ion batteries.},

keywords = {Anodes, Density Functional Theory, Lithium ion batteries, SiC nanowires},

pubstate = {published},

tppubtype = {article}

}

@article{JIMENEZSANCHEZ2023102745,

title = {Surface Li effects on the electronic properties of GaAs nanowires: A first principles approach},

author = {Ricardo Jim\'{e}nez-S\'{a}nchez and Sara E. P\'{e}rez-Figueroa and Alejandro Trejo-Ba\~{n}os and \'{A}lvaro Miranda and Fernando Salazar and Miguel Cruz-Irisson},

url = {https://www.sciencedirect.com/science/article/pii/S2468023023001153},

doi = {https://doi.org/10.1016/j.surfin.2023.102745},

issn = {2468-0230},

year  = {2023},

date = {2023-01-01},

journal = {Surfaces and Interfaces},

volume = {38},

pages = {102745},

abstract = {The quest for the improvement of Li-Ion batteries has directed attention towards semiconductor nanostructures, like nanowires. However, the surface interactions and effects of Li on the electronic properties of these nanostcrutures has been less explored. Especially the possible modifications to the properties of GaAs nanowires that arise from having Li on its surface have been seldom studied. In this work, we employed Density Functional Theory to study the effects of surface Li on the electronic properties of H passivated GaAs nanowires grown along the [111] direction. To determinate the isolated effects of Li on either surface Ga or As, only Li bonded to either Ga[GaAsNW_Ga-Li] or As[GaAsNW_As-Li] were considered, and up to 6 Li were placed on the respective nanowire surfaces. The results indicate that the energy gap is a function of the Li concentration, the nanowire diameter and the placement of Li on the nanowire surface. The binding energy is independent of the number of Li on the nanowire surface, where the GaAsNW_Ga-Li has slower binding energies compared to the GaAsNW_As-Li, but the binding energies and band gaps in both cases are high, which would hinder the application of these nanowires in Li ion batteries.},

keywords = {DFT, GaAs nanowires, Surface passivation},

pubstate = {published},

tppubtype = {article}

}

@article{SANTANA2023102584,

title = {Highly sensitive amphetamine drug detection based on silicon nanowires: Theoretical investigation},

author = {Jos\'{e} Eduardo Santana and Akari Narayama Sosa and Francisco De Santiago and \'{A}lvaro Miranda and Luis Antonio P\'{e}rez and Alejandro Trejo and Fernando Salazar and Miguel Cruz-Irisson},

url = {https://www.sciencedirect.com/science/article/pii/S2468023022008392},

doi = {https://doi.org/10.1016/j.surfin.2022.102584},

issn = {2468-0230},

year  = {2023},

date = {2023-01-01},

journal = {Surfaces and Interfaces},

volume = {36},

pages = {102584},

abstract = {Amphetamine (AA) is used in some therapeutic treatments, but it is also one of the most widely used illicit drugs. Therefore, a correct tracking of AA in various environments is crucial for its controlled distribution even inside the human body. However, current sensors are still too large to fit inside the human body and their biocompatibility is still deficient. Since the discovery of nanostructures, especially silicon nanowires (SiNWs), the possibilities of sensors inside the human body have increased due to their enhanced properties and biocompatibility. However, theoretical studies about the capabilities of SiNWs with surface modifications as sensing materials are still scarce. Using Density Functional Theory, we investigate the effects of amphetamine adsorption on the work function, and other electronic and structural properties, of pristine and modified SiNWs. Two types of modifications were studied, i.e., substitutional doping with B, Al, and Ga atoms and surface functionalization with the same species. The adsorption energies of the amphetamine molecule are larger for the doped nanowires, followed by the functionalized ones, and lastly, the undoped Si nanowire.This study shows that undoped, doped, and functionalized SiNWs are excellent candidates for AA sensing, with B being the best chemical species for improving AA adsorption for both doped and functionalized schemes.},

keywords = {Amphetamine, DFT, Doping, Drug, Sensor, Silicon nanowires},

pubstate = {published},

tppubtype = {article}

}

@article{BERMEOCAMPOS2023157481,

title = {Surface morphology effects on the mechanical and electronic properties of halogenated porous 3C-SiC: A DFT study},

author = {R. Bermeo-Campos and K. Madrigal-Carrillo and S. E. Perez-Figueroa and M. Calvino and A. Trejo and F. Salazar and A. Miranda and M. Cruz-Irisson},

url = {https://www.sciencedirect.com/science/article/pii/S0169433223011595},

doi = {https://doi.org/10.1016/j.apsusc.2023.157481},

issn = {0169-4332},

year  = {2023},

date = {2023-01-01},

journal = {Applied Surface Science},

volume = {631},

pages = {157481},

abstract = {Silicon carbide nanostructures have been widely studied due to their potential technological applications. However, the theoretical characterization, especially the effect of the surface on the mechanical properties of this material is still underexplored. In this work, we report the electronic and mechanical properties of 3C-SiC nanopores with different pore surfaces and different passivation schemes using a density functional theory approach and the supercell technique. The nanopores were modeled by removing columns of atoms in the [001] direction, thus creating four types of pores, two with an Only C or Si pore and two with a C or Si-Rich pore surface. All surfaces were passivated with hydrogen, then some atoms of H were replaced with fluorine and chlorine. Results show that pores with a higher concentration of C on the surface have a larger bandgap compared with the Si cases. Moreover, only a few changes can be observed due to passivation. For the mechanical properties the Bulk and Young’s modulus were calculated and show that the Only C structures were the most brittle and, for almost all the pores, the H + Cl passivation improve the Bulk modulus.},

keywords = {DFT, electronic properties, Halogens, Mechanical properties, Porous SiC},

pubstate = {published},

tppubtype = {article}

}

@article{ARELLANO2023106704,

title = {DFT investigation of metal-decorated silicon carbide nanosheets for the adsorption of NH3},

author = {Lucia G. Arellano and Brandom J. Cid and Jos\'{e} E. Santana and Francisco De Santiago and \'{A}lvaro Miranda and Alejandro Trejo and Fernando Salazar and Luis A. P\'{e}rez and Miguel Cruz-Irisson},

url = {https://www.sciencedirect.com/science/article/pii/S2352492823013958},

doi = {https://doi.org/10.1016/j.mtcomm.2023.106704},

issn = {2352-4928},

year  = {2023},

date = {2023-01-01},

journal = {Materials Today Communications},

volume = {36},

pages = {106704},

abstract = {The threat that ammonia (NH3) poses in various human activity environments drives the necessity of sensors of higher sensitivity. Two-dimensional (2D) materials have attracted attention for this particular purpose, with 2D silicon carbide being one prospect for this application. However, this potential use has been relatively unexplored. In this work, we study the adsorption of NH3 on pristine and metal (Li, Na, Mg, Ca, Ag, Au, Cu, Pd, and Ti) decorated silicon carbide monolayers (2D-SiC) using a first-principles approach based on Density-Functional Theory. Energetic analyses were performed to determine the enhancement or deterioration of the NH3 adsorption capacities of the 2D-SiC. The results show that the Ag- and Au-decorated monolayers are the best candidates for NH3 capturing due to the large adsorption energies found in these systems.},

keywords = {2D materials, Ammonia, DFT, Monolayer, Sensor, Silicon carbide},

pubstate = {published},

tppubtype = {article}

}

@article{Sosa2022,

title = {NH3 capture and detection by metal-decorated germanene: a DFT study},

author = {Akari Narayama Sosa and Jos\'{e} Eduardo Santana and \'{A}lvaro Miranda and Luis Antonio P\'{e}rez and Alejandro Trejo and Fernando Salazar and Miguel Cruz-Irisson},

url = {https://doi.org/10.1007/s10853-022-06955-w},

doi = {10.1007/s10853-022-06955-w},

issn = {1573-4803},

year  = {2022},

date = {2022-05-01},

journal = {Journal of Materials Science},

volume = {57},

number = {18},

pages = {8516-8529},

abstract = {We report an investigation of the adsorption of ammonia (NH3) on pristine, alkali (Li, Na, K), alkaline earth (Mg, Ca), and transition metal (Sc, Pd, and Ag) decorated germanene using a first-principles approach based on density-functional theory (DFT). The most stable adsorption geometries, adsorption energies, and charge transfers of NH3 adsorbed on pristine and metal-decorated germanene are thoroughly discussed. First, the NH3 adsorption on pristine germanene was considered, and subsequently, the NH3 adsorption on metal-decorated germanene was studied. Our calculations found that the NH3 is weakly adsorbed on pristine germanene. All metals improved the adsorption properties of pristine germanene. In particular, Sc, Mg, and Li atoms showed significantly enhanced interactions between NH3 and germanene. In general, the electronic and adsorption properties demonstrated that metal-decorated germanene is superior to pristine germanene for the adsorption of NH3 molecules. Changes in the work function due to adsorption of NH3 molecule on the metal-decorated germanene were also calculated. Adsorption energy and desorption time results show that Sc-decorated germanene could trap this dangerous molecule at room temperature.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{https://doi.org/10.1002/er.8378,

title = {Tunable electronic properties of silicon nanowires as sodium-battery anodes},

author = {Lucia Guadalupe Arellano and Fernando Salazar and \'{A}lvaro Miranda and Alejandro Trejo and Luis Antonio P\'{e}rez and Jun Nakamura and Miguel Cruz-Irisson},

url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/er.8378},

doi = {https://doi.org/10.1002/er.8378},

year  = {2022},

date = {2022-01-01},

journal = {International Journal of Energy Research},

volume = {46},

number = {12},

pages = {17151-17162},

abstract = {Summary Although materials for lithium-ion batteries have been extensively studied, alternatives such as sodium-ion batteries have acquired a renewed interest due to the abundance of Na compared to Li. However, the investigation of new materials for Na battery anodes is still in progress. In this work, a density functional study of the electronic properties of hydrogen passivated silicon nanowires (H-SiNWs) with interstitial Na atoms is presented. The studied H-SiNWs are grown along the [001] crystallographic direction and have a diameter close to 2.5 nm. Moreover, from 1 to 12 interstitial Na atoms per H-SiNW unit cell were considered. The results reveal that the former semiconducting nanowires become metallic for all the Na concentrations, even for the case of a single Na atom. The formation energy diminishes as a function of the concentration of Na atoms, revealing a loss of energetic stability since the size of the Na atoms strongly modify the Si-Si bonds. Moreover, when the Na atoms are removed from the metallic sodiated H-SiNW and relaxed again, for concentrations between 1 and 8 Na atoms, the resulting structure corresponds to the original H-SiNW one, indicating that the Na insertion/extraction process is a reversible one. In contrast, for concentrations between 10 and 12 Na atoms, the structure that results from removing of these Na atoms has a different atomic arrangement, in comparison with the initial H-SiNW, and also smaller band gap. These results open the possibility to consider the H-SiNWs as potential anodic materials in sodium rechargeable batteries.},

keywords = {DFT, Silicon nanowires, sodium-ion batteries},

pubstate = {published},

tppubtype = {article}

}

@article{CUEVAS2022115372,

title = {Theoretical approach to the phonon modes of GaSb nanowires},

author = {J. L. Cuevas and M. Ojeda and M. Calvino and A. Trejo and F. Salazar and A. Miranda and L. A. Perez and M. Cruz-Irisson},

url = {https://www.sciencedirect.com/science/article/pii/S1386947722002077},

doi = {https://doi.org/10.1016/j.physe.2022.115372},

issn = {1386-9477},

year  = {2022},

date = {2022-01-01},

journal = {Physica E: Low-dimensional Systems and Nanostructures},

volume = {143},

pages = {115372},

abstract = {Gallium Antimonide nanowires (GaSbNWs) have attracted much attention due to their possible applications in mid infrared detectors, however, there are only few theoretical investigations about this material and almost none regarding its vibrational properties. In this work the phonon modes of GaSbNWs were studied using the density functional theory with the finite displacement supercell scheme. The nanowires are modeled by removing atoms outside from a circumference along the [1 1 1] direction. All surface dangling bonds were passivated with hydrogen atoms. The results show that the expected red-shift of the highest frequency modes of GaSb are hindered by low frequency H bond bending modes. Three clearly distinguishable frequency intervals were observed: One with vibrations whose main contribution come from the Ga and Sb nanowire atoms, the second interval with main contributions from H bending modes and finally a high frequency interval where the main contributions come from H stretching modes. Also, it was observed that the radial breathing mode (RBM) decreases when the nanowire diameter increases, while the contrary tendency is observed with their specific heat (the specific heat increases as the nanowire diameter increases), except in the low temperature region where the lower diameters have higher specific heat values. These results could be important for the characterization of these nanowires with IR and Raman techniques.},

keywords = {DFT, Gallium Antimonide, Nanowires, Phonons},

pubstate = {published},

tppubtype = {article}

}

@article{https://doi.org/10.1002/er.7754,

title = {Sodium effects on the electronic and structural properties of porous silicon for energy storage},

author = {Israel Gonz\'{a}lez and Jorge Pilo and Alejandro Trejo and \'{A}lvaro Miranda and Fernando Salazar and Roc\'{i}o Nava and Miguel Cruz-Irisson},

url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/er.7754},

doi = {https://doi.org/10.1002/er.7754},

year  = {2022},

date = {2022-01-01},

journal = {International Journal of Energy Research},

volume = {46},

number = {7},

pages = {8760-8780},

abstract = {Summary Porous silicon is a promising anode material in Na-ion batteries, however, there are still no theoretical studies describing the Na storage mechanism within this material. In this work, we present a density functional theory study on the effects of interstitial and substitutional Na atoms on the electronic and structural properties of hydrogen-passivated porous silicon (pSiH). The results show that the substitutional Na reduces the band gap, while the interstitial Na induces metallic properties on the pSiH. The diffusion analysis by the nudged elastic band scheme, reveals that the interstitial Na atoms migrate from the silicon lattice to the pore surface, while the pSiH energy barrier decreases by 20.42% relative to the bulk silicon energy barrier value. Finally, the hydrogenated surface proves to be beneficial for both Na adsorption and diffusion. These results could be important for understanding the storage and diffusion mechanism of Na on pSiH .},

keywords = {DFT, Na-batteries, NEB, porous silicon},

pubstate = {published},

tppubtype = {article}

}

@article{CID202241310,

title = {Enhanced reversible hydrogen storage performance of light metal-decorated boron-doped siligene: A DFT study},

author = {Brandom Jhoseph Cid and Akari Narayama Sosa and \'{A}lvaro Miranda and Luis Antonio P\'{e}rez and Fernando Salazar and Arturo I. Mtz-Enriquez and Miguel Cruz-Irisson},

url = {https://www.sciencedirect.com/science/article/pii/S0360319922012332},

doi = {https://doi.org/10.1016/j.ijhydene.2022.03.153},

issn = {0360-3199},

year  = {2022},

date = {2022-01-01},

journal = {International Journal of Hydrogen Energy},

volume = {47},

number = {97},

pages = {41310-41319},

abstract = {The use of nanomaterials for hydrogen storage could play a very important role in the large-scale utilization of hydrogen as an energy source. However, nowadays several potential hydrogen storage nanomaterials do not have a large gravimetric density and stability at room temperature. In this work, we have investigated the hydrogen storage performances of Na-, K- and Ca-decorated B-doped siligene monolayer (BSiGeML) using density functional theory calculations. The results show that boron doping improves the interaction between the metal adatom and the siligene monolayer (SiGeML). The K- and Ca-decorated BSiGeMLs can bind up to seven H2 molecules per metal adatom, whereas Na-decorated BSiGeML only adsorb four H2 molecules per adsorption site. The effect of temperature and pressure on the hydrogen storage capacity of BSiGeMLs was also evaluated. At room temperature, all the H2 molecules adsorbed on Na-, and Ca-decorated BSiGeML are stable at mild pressure. The metal decoration of both sides of BSiGeML may lead to hydrogen gravimetric densities exceeding the target of 5.5 wt% proposed by DOE for the year 2025. K- and Ca-decorated BSiGeML could be efficient hydrogen molecular storage media compared to undoped SiGeML and other 2D pristine materials.},

note = {Future Energy \& Materials},

keywords = {2D materials, Doping, Energy storage, Hydrogen storage, Siligene},

pubstate = {published},

tppubtype = {article}

}

@article{GONZALEZ2022110956,

title = {Low lattice thermal conductance obtained by controllable quasiperiodic long-range disorder in ternary atomic ribbons with rock-salt structure},

author = {J. E. Gonz\'{a}lez and C\'{e}sar G. Galv\'{a}n and F. Salazar and M. Cruz-Irisson},

url = {https://www.sciencedirect.com/science/article/pii/S0022369722003791},

doi = {https://doi.org/10.1016/j.jpcs.2022.110956},

issn = {0022-3697},

year  = {2022},

date = {2022-01-01},

journal = {Journal of Physics and Chemistry of Solids},

volume = {170},

pages = {110956},

abstract = {To achieve thermoelectric devices with high efficiency requires developing routes to modulate the vibrational properties of semiconductor materials that allow obtaining low lattice thermal conductance. Several efforts have been made to understand the thermal conduction of thermoelectric materials. In particular, semiconductors with rock-salt structure are promising for thermoelectric applications because of the possibility of modifying their thermal properties by composition and the huge quantity of compounds that can be built with this kind of structure. In this work, we investigate how the vibrational properties of ternary atomic ribbons with rock-salt structure can be controlled by Fibonacci long-range mass disorder structure. The study is performed through a real space analysis using the thermal Kubo\textendashGreenwood formula and the Born interaction potential. The results show how the transmission of acoustical phonons with low frequency can be blocked by Fibonacci structures, leading to a progressive decrease of the lattice thermal conductance, which is favorable for thermoelectric applications.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{ARELLANO202129261,

title = {Ab initio study of hydrogen storage on metal-decorated GeC monolayers},

author = {Lucia Guadalupe Arellano and Francisco De Santiago and \'{A}lvaro Miranda and Luis Antonio P\'{e}rez and Fernando Salazar and Alejandro Trejo and Jun Nakamura and Miguel Cruz-Irisson},

url = {https://www.sciencedirect.com/science/article/pii/S036031992101555X},

doi = {https://doi.org/10.1016/j.ijhydene.2021.04.135},

issn = {0360-3199},

year  = {2021},

date = {2021-01-01},

journal = {International Journal of Hydrogen Energy},

volume = {46},

number = {57},

pages = {29261-29271},

abstract = {Bidimensional nanostructures have been proposed as hydrogen-storage systems owing to their large surface-to-volume ratios. Germanium carbide monolayers (GeC-MLs) can offer attractive opportunities for H2 adsorption compared to graphene. However, this possibility has not been explored in detail. In this work, the adsorption of H2 molecules on GeC-MLs decorated with alkali metal (AM) and alkaline earth metal (AEM) adatoms was investigated using the density functional theory. Results showed that the AM adatoms were chemisorbed on the GeC-ML, whereas AEM adatoms were physisorbed. The H2 molecules presented negligible adsorption energies on the weakly adsorbed AEM adatoms. Conversely, the AM adatoms improved the H2 adsorption, possibly due to a large charge transfer from the adatoms to the GeC-ML. The potassium-decorated GeC-ML exhibited the most optimal H2 storage capacity, adsorbing up to six molecules and with a lower possibility of forming metal clusters than the other studied cases. These results may aid in the development of new efficient hydrogen-storage materials.},

note = {HYDROGEN ENERGY SYSTEMS},

keywords = {2D materials, Alkali metals, DFT, Germanium carbide, Hydrogen storage, Renewable energy},

pubstate = {published},

tppubtype = {article}

}

@article{SOSA202129348,

title = {Light metal functionalized two-dimensional siligene for high capacity hydrogen storage: DFT study},

author = {Akari Narayama Sosa and Brandom Jhoseph Cid and \'{A}lvaro Miranda and Luis Antonio P\'{e}rez and Fernando Salazar and Alejandro Trejo and Miguel Cruz-Irisson},

url = {https://www.sciencedirect.com/science/article/pii/S0360319920340246},

doi = {https://doi.org/10.1016/j.ijhydene.2020.10.175},

issn = {0360-3199},

year  = {2021},

date = {2021-01-01},

journal = {International Journal of Hydrogen Energy},

volume = {46},

number = {57},

pages = {29348-29360},

abstract = {In this work, the hydrogen storage capacities of two-dimensional siligene (2D-SiGe) functionalized with alkali metal (AM) and alkali-earth metal (AEM) atoms were studied using density functional theory calculations. One AM (Li, Na, K) or AEM (Be, Mg, Ca) atom was placed on the 2D-SiGe surface, and several H2 molecules were placed in the vicinity of the adatom. The results demonstrate that the most favorable siligene site for the adsorption of Li, Na, K and Be atoms is the hollow site, while for the Mg and Ca atoms is the down site. The AM atoms are the only ones with considerable binding energies on the SiGe nanosheets. Pristine 2D-SiGe slightly adsorbs one H2 molecule per hollow site and, therefore, it is not suitable for hydrogen storage. In some of the AM- and AEM-decorated 2D-SiGe, several hydrogen molecules can be physisorbed. In particular, the Na-, K- and Ca-functionalized 2D-SiGe can adsorb six hydrogen molecules, whereas Li and Mg atoms adsorbed three hydrogen molecules, and the Be adatom only adsorbed one hydrogen molecule. The complexes formed by hydrogen molecules adsorbed on the analyzed metal decorated 2D-SiGe are energetically stable, indicating that functionalized 2D-SiGe could be an efficient molecular hydrogen storage media.},

note = {HYDROGEN ENERGY SYSTEMS},

keywords = {2D materials, Alkali metals, DFT, Hydrogen storage, Renewable energy, Siligene},

pubstate = {published},

tppubtype = {article}

}

@article{SOSA202120245,

title = {Alkali and transition metal atom-functionalized germanene for hydrogen storage: A DFT investigation},

author = {Akari Narayama Sosa and Francisco Santiago and \'{A}lvaro Miranda and Alejandro Trejo and Fernando Salazar and Luis Antonio P\'{e}rez and Miguel Cruz-Irisson},

url = {https://www.sciencedirect.com/science/article/pii/S0360319920315329},

doi = {https://doi.org/10.1016/j.ijhydene.2020.04.129},

issn = {0360-3199},

year  = {2021},

date = {2021-01-01},

journal = {International Journal of Hydrogen Energy},

volume = {46},

number = {38},

pages = {20245-20256},

abstract = {In this work, we have performed density functional theory-based calculations to study the adsorption of H2 molecules on germanene decorated with alkali atoms (AM) and transition metal atoms (TM). The cohesive energy indicates that interaction between AM (TM) atoms and germanene is strong. The values of the adsorption energies of H2 molecules on the AM or TM atoms are in the range physisorption. The K-decorated germanene has the largest storage capacity, being able to bind up to six H2 molecules, whereas the Au and Na atoms adsorbed five and four H2 molecules, respectively. Li and Ag atoms can bind a maximum of three H2 molecules, while Cu-decorated germanene only adsorbed one H2 molecule. Formation energies show that all the studied cases of H2 molecules adsorbed on AM and TM atom-decorated germanene are energetically favorable. These results indicate that decorated germanene can serve as a hydrogen storage system.},

note = {International Journal of Hydrogen Energy Special Issue devoted to the 32nd International Conference ECOS 2019},

keywords = {2D materials, Decoration, Density Functional Theory, Germanene, Hydrogen storage, Renewable energy storage},

pubstate = {published},

tppubtype = {article}

}

@article{ARELLANO202120266,

title = {Hydrogen storage capacities of alkali and alkaline-earth metal atoms on SiC monolayer: A first-principles study},

author = {Luc\'{i}a G. Arellano and Francisco Santiago and \'{A}lvaro Miranda and Fernando Salazar and Alejandro Trejo and Luis A. P\'{e}rez and Miguel Cruz-Irisson},

url = {https://www.sciencedirect.com/science/article/pii/S0360319920310144},

doi = {https://doi.org/10.1016/j.ijhydene.2020.03.078},

issn = {0360-3199},

year  = {2021},

date = {2021-01-01},

journal = {International Journal of Hydrogen Energy},

volume = {46},

number = {38},

pages = {20266-20279},

abstract = {A detailed theoretical Density-Functional-Theory-based investigation of hydrogen adsorption on silicon carbide monolayers (SiC-ML) decorated with alkali and alkaline-earth metal atoms is presented. The results show that the favourable position for all adsorbed metal atoms is above a Si atom. These metal atoms are chemisorbed to the SiC-ML, except for Mg which is physisorbed. The adsorbed atoms act in turn as adsorption sites for H2 molecules. The single-sided K-functionalized SiC-ML can store up to six H2 molecules. For double-side K-decorated SiC-ML, up to ten H2 molecules can be captured. In all cases, the H2 molecules are physisorbed. This is beneficial because the breaking of chemical bonds, which otherwise would be needed to make use of the stored H2, is energetically expensive. These results find decorated SiC-ML as a promising material for hydrogen storage systems.},

note = {International Journal of Hydrogen Energy Special Issue devoted to the 32nd International Conference ECOS 2019},

keywords = {2D monolayers, Adsorption energy, DFT, Hydrogen storage, Silicon carbide},

pubstate = {published},

tppubtype = {article}

}

@article{D0MA00884B,

title = {Fluorinated porous silicon as sensor material for environmentally toxic gases: a first-principles study},

author = {Jos\'{e} Eduardo Santana and Francisco Santiago and \'{A}lvaro Miranda and Luis Antonio P\'{e}rez and Fernando Salazar and Alejandro Trejo and Miguel Cruz-Irisson},

url = {http://dx.doi.org/10.1039/D0MA00884B},

doi = {10.1039/D0MA00884B},

year  = {2021},

date = {2021-01-01},

journal = {Mater. Adv.},

volume = {2},

issue = {3},

pages = {1072-1082},

publisher = {RSC},

abstract = {By using Density Functional Theory, the effect of adsorbed gas molecules on the electronic properties of fluorine passivated porous silicon (pSi) is investigated. A silicon nanopore is created by removing columns of atoms along the [001] crystallographic axis from a supercell of the bulk Si crystal. The Si dangling bonds of the generated pore are saturated with fluorine atoms except for the sites where gas molecules of NO, NO2 and SO2 are adsorbed. The adsorption energies, electronic densities of states and band structures of the different complexes formed by the nanopore and the adsorbed molecules are calculated and compared with previously reported results obtained for hydrogen-passivated pSi. The energy band gaps of the pSi-molecule complexes depend on the adsorbed species, opening the possibility of gas molecule recognition. The molecule adsorption energy is stronger for NO2. The understanding of molecule adsorption on silicon nanopores could lead to the development of novel sensing devices of environmentally hazardous gases.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{CID2021129743,

title = {Hydrogen storage on metal decorated pristine siligene and metal decorated boron-doped siligene},

author = {Brandom Jhoseph Cid and Akari Narayama Sosa and \'{A}lvaro Miranda and Luis A. P\'{e}rez and Fernando Salazar and Miguel Cruz-Irisson},

url = {https://www.sciencedirect.com/science/article/pii/S0167577X21004390},

doi = {https://doi.org/10.1016/j.matlet.2021.129743},

issn = {0167-577X},

year  = {2021},

date = {2021-01-01},

journal = {Materials Letters},

volume = {293},

pages = {129743},

abstract = {In this work, two schemes were studied to improve hydrogen storage on metal decorated two-dimensional siligene (SiGe). In the first one, Li-, Sc- and Ti atoms are adsorbed on pristine siligene monolayer (SiGeML), while in the second scheme Li-, Sc- and Ti atoms decorated B-doped siligene monolayer (BSiGeML). The results show that boron doping improves the interaction between metal atom and SiGeML. The numerical results indicate that H2 molecules are slightly physisorbed on the Li atom, while they are strongly physisorbed on Sc- and Ti-decorated monolayers. The Sc-decorated BSiGeML and Sc-decorated SiGeML have the highest hydrogen storage capacity, both systems were capable of storing five H2 molecules, whereas Li- and Ti-decorated BSiGeML and Ti-decorated SiGeML can adsorb up to four H2 molecules. SiGeML and BSiGeML decorated with Sc atoms could have potential as efficient hydrogen molecular storage media.},

keywords = {2D materials, Doping, Energy storage, Hydrogen storage, Siligene},

pubstate = {published},

tppubtype = {article}

}

@article{Bermeo_2020,

title = {Effects of Surface in the IR and Raman Spectrum of Porous Silicon Carbide},

author = {R Bermeo and L. Arellano and A Trejo and F Salazar and M. Calvino and A Miranda and M Cruz-Irisson},

url = {https://dx.doi.org/10.1088/1757-899X/840/1/012009},

doi = {10.1088/1757-899X/840/1/012009},

year  = {2020},

date = {2020-05-01},

journal = {IOP Conference Series: Materials Science and Engineering},

volume = {840},

number = {1},

pages = {012009},

publisher = {IOP Publishing},

abstract = {Porous Silicon carbide has been identified as an attractive material for its use as electrode in supercapacitors, however the theoretical investigations about its properties, specially its vibrational properties, are still scarce. In this work the effect of the Si-C surface ratio on the vibrational properties, IR and Raman spectrum of porous silicon carbide was studied using the first principles density functional perturbation theory. The porous structures were modelled by removing atoms in the [001] direction from an otherwise perfect SiC crystal using the supercell scheme. The morphology of the pores was chosen so there would be more Si or C in the pore surface. The results show that the vibrational properties, and thus the IR and Raman spectrum of the porous SiC change depending if the pore surface is either Si or C rich, having the Si-rich pores more low frequency modes due to its higher mass. Also, the effects of phonon confinement are lessened by the effect of surface passivation, thus indicating that the surface plays an important role in the IR and Raman characterization of these structures.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Arellano_2020,

title = {Electronic properties of [111] hydrogen passivated Ge nanowires with surface substitutional lithium},

author = {L G Arellano and F Salazar and A Trejo Ba\~{n}os and A Miranda and L A P\'{e}rez and M Cruz-Irisson},

url = {https://dx.doi.org/10.1088/1757-899X/840/1/012004},

doi = {10.1088/1757-899X/840/1/012004},

year  = {2020},

date = {2020-05-01},

journal = {IOP Conference Series: Materials Science and Engineering},

volume = {840},

number = {1},

pages = {012004},

publisher = {IOP Publishing},

abstract = {In this work, a density functional theory study of the lithium (Li) effects on the properties of hydrogenated germanium nanowires (H-GeNWs) is developed. In particular, the electronic band structures, densities of states, formation energies, and Li binding energies of H-GeNWs grown along the [111] crystallographic direction with a diamond structure for different concentrations of surface substitutional Li atoms were studied. Ge nanowires with hexagonal cross sections and three different diameters were considered. The results indicate that all studied H-GeNWs maintain a semiconducting behaviour and the size of the energy band gap is a function of the diameter and the concentration of substitutional surface Li atoms. The formation energy analysis reveals than the energy stability of the nanowires increases when the nanowire diameter and the concentration of Li atoms augment. The results of this work give insight of how the electronic properties of H-GeNWs change during the charging process and open the possibility to incorporate them as electrodes in Li-ion batteries.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{ORNELASCRUZ2020109619,

title = {DFT-based study of the bulk tin mixed-halide CsSnI3-xBrx perovskite},

author = {I. Ornelas-Cruz and A. Trejo and R. Oviedo-Roa and F. Salazar and E. Carvajal and A. Miranda and M. Cruz-Irisson},

url = {https://www.sciencedirect.com/science/article/pii/S0927025620301105},

doi = {https://doi.org/10.1016/j.commatsci.2020.109619},

issn = {0927-0256},

year  = {2020},

date = {2020-01-01},

journal = {Computational Materials Science},

volume = {178},

pages = {109619},

abstract = {Metal-halide perovskites compounds, such as CsSnX3 (X = halogen), have attracted a lot of attention as a photovoltaic material due to their astonishing optoelectronic properties, nevertheless, the improvement of its efficiency is still an issue. It has been observed that the mixing of halogens in the perovskite structure increases the compound stability. However, theoretical studies of the effects of this mixing are scarce; by understanding the most stable mixing positions it would be possible to enhance the stability of these structures, which in turn it would help to enhance the performance of a perovskite-based photovoltaic device. Thus, a Density Functional Theory study was performed on the CsSnI3-xBrx perovskite as a function of the bromine concentration (0 ≤ x ≤ 3). The distortions of the octahedral array and the energy gap of each system studied are highly dependent on the position of bromine atoms within the unit-cell. It was observed that stable compounds could be found at x = 0.5, 1.0, and 2.0 due to the strengthening of the metal-halogen bonds. These results could explain the literature-reported enhance of the performance, as a photovoltaic material, of CsSnI3-xBrx with respect to CsSnI3. Besides, non-covalent interactions between halogens and Cs atoms were found. Different energies attributed to such interactions were calculated and revealed that the off-centering of Cs atoms are driven by the countering effect of the I-(1−δ)-Sn-Br-(1+δ) polar bonds within CsSnI3-xBrx. These results give an insight of the properties of the CsSnI3-xBrx alloy and its stability which could be beneficial to the rising field of perovskite photovoltaics.},

keywords = {DFT, Metal-halide, Mixed-halide, Perovskite, Photovoltaic},

pubstate = {published},

tppubtype = {article}

}

@article{GONZALEZ202026321,

title = {Theoretical modelling of porous silicon decorated with metal atoms for hydrogen storage},

author = {Israel Gonz\'{a}lez and Francisco De Santiago and Luc\'{i}a G. Arellano and \'{A}lvaro Miranda and Alejandro Trejo and Fernando Salazar and Miguel Cruz-Irisson},

url = {https://www.sciencedirect.com/science/article/pii/S0360319920318784},

doi = {https://doi.org/10.1016/j.ijhydene.2020.05.097},

issn = {0360-3199},

year  = {2020},

date = {2020-01-01},

journal = {International Journal of Hydrogen Energy},

volume = {45},

number = {49},

pages = {26321-26333},

abstract = {There is experimental evidence suggesting that metal adatoms enhance the physisorption of hydrogen molecules in porous silicon. However, theoretical reports about the physical properties for this material to be suitable for hydrogen storage are scarce. Thus, in this work we employ Density Functional Theory to study the effects of decoration with metals on the hydrogen-adsorption properties on hydrogen-passivated porous silicon. The results indicate that lithium and palladium decorating atoms are strongly bonded to the porous silicon\textemdashpreventing the adverse effects of clusterization\textemdashwhile beryllium is not. Lithium and palladium exhibit physisorption capacity up to 5 and 4 hydrogen molecules per adatom, respectively. In contrast, adsorption of hydrogen molecules in beryllium is too weak as the adatom is not chemisorbed on the surface of the pore. The hydrogen passivation of the pore surface proves to be beneficial for a strong chemisorption of the decorating atoms.},

note = {Progress in Hydrogen Production and Utilization},

keywords = {Beryllium, DFT, Hydrogen storage, Lithium, Palladium, porous silicon},

pubstate = {published},

tppubtype = {article}

}

@article{https://doi.org/10.1002/jcc.26421,

title = {Effects of lithium on the electronic properties of porous Ge as anode material for batteries},

author = {Akari Narayama Sosa and Israel Gonz\'{a}lez and Alejandro Trejo and \'{A}lvaro Miranda and Fernando Salazar and Miguel Cruz-Irisson},

url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/jcc.26421},

doi = {https://doi.org/10.1002/jcc.26421},

year  = {2020},

date = {2020-01-01},

journal = {Journal of Computational Chemistry},

volume = {41},

number = {31},

pages = {2653-2662},

abstract = {Abstract Recently, the need of improvement of energy storage has led to the development of Lithium batteries with porous materials as electrodes. Porous Germanium (pGe) has shown promise for the development of new generation Li-ion batteries due to its excellent electronic, and chemical properties, however, the effect of lithium in its properties has not been studied extensively. In this contribution, the effect of surface and interstitial Li on the electronic properties of pGe was studied using a first-principles density functional theory scheme. The porous structures were modeled by removing columns of atoms in the [001] direction and the surface dangling bonds were passivated with H atoms, and then replaced with Li atoms. Also, the effect of a single interstitial Li in the Ge was analyzed. The transition state and the diffusion barrier of the Li in the Ge structure were studied using a quadratic synchronous transit scheme.},

keywords = {Density Functional Theory, electronic properties, Li-ion batteries, porous germanium, transition state},

pubstate = {published},

tppubtype = {article}

}

@article{Salazar2019,

title = {Interstitial sodium and lithium doping effects on the electronic and mechanical properties of silicon nanowires: a DFT study},

author = {F. Salazar and A. Trejo-Ba\~{n}os and A. Miranda and L. A. P\'{e}rez and M Cruz-Irisson},

url = {https://doi.org/10.1007/s00894-019-4239-5},

doi = {10.1007/s00894-019-4239-5},

issn = {0948-5023},

year  = {2019},

date = {2019-11-09},

journal = {Journal of Molecular Modeling},

volume = {25},

number = {11},

pages = {338},

abstract = {In this work, we present a theoretical study of the electronic band structure and the Young's modulus of hydrogen-passivated silicon nanowires (H-SiNWs), grown along the [110] crystallographic direction, as a function of the concentration of interstitial sodium (Na) and lithium (Li) atoms. The study is performed using the supercell scheme and the density functional theory (DFT), within the local density approximation (LDA). The results show that the presence of Na or Li atoms closes the former semiconducting band gap of the H-SiNWs and shifts the Fermi energy into the conduction band. The transition from semiconductor to metal occurs as soon as a single Na or Li atom is added to the nanowire and the number of occupied states near the Fermi level is larger for the H-SiNWs with Li atoms in comparison with those nanowires with the same concentration of Na atoms. The calculated formation energies reveal that the system becomes less stable when the concentration of Na and Li atoms augments. Moreover, the obtained binding energies indicate that Si--Li and Si--Na bonds are formed. It is worth mentioning that the binding energies of H-SiNWs with interstitial Li atoms are larger than those corresponding to the H-SiNWs with interstitial Na atoms. On the other hand, the Young's moduli of H-SiNWs with Na atoms are lower than those of pure H-SiNWs and their values diminish when the concentration of Na atoms increases. In contrast, Young's moduli of H-SiNWs present a non-monotonic behavior as a function of the concentration of interstitial Li atoms and for the largest studied concentration the nanowire fractures. These results give insight into the changes that electronic and mechanical properties of H-SiNWs suffer during the charge-discharge process, which should be taken into account in the design of electrodes of Na or Li-ion batteries.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Gonz\'{a}lez_2019,

title = {Confinement effect on the low temperature specific heat for ultrathin silicon nanowires: a first principles study},

author = {I Gonz\'{a}lez and M Calvino and A Trejo and F Salazar and M Cruz-Irisson},

url = {https://dx.doi.org/10.1088/1361-648X/ab2dd4},

doi = {10.1088/1361-648X/ab2dd4},

year  = {2019},

date = {2019-07-01},

journal = {Journal of Physics: Condensed Matter},

volume = {31},

number = {42},

pages = {425303},

publisher = {IOP Publishing},

abstract = {This work studied the phonon confinement effects at the low temperature specific heat of Si nanowires from first principles using density functional perturbation theory. The nanowires were modeled in the [0 0 1] direction for three different diameters, with the largest cross section being approximately 10 r{A}. The results indicate the specific heat can be described at low temperatures using a third-grade polynomial of the form cv = λT + βT2 + γT3, where the coefficients of quadratic and cubic terms are almost nonexistent for small diameters. These terms begin to have relevance at larger diameters. Further analysis shows λ > β > γ, which shows the phonon confinement (λ) and surface atoms (β) become more important than the volumetric contribution (γ) for ultrathin nanowires at low temperatures.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{DESANTIAGO2019438,

title = {Lithiation effects on the structural and electronic properties of Si nanowires as a potential anode material},

author = {F. De Santiago and J. E. Gonz\'{a}lez and A. Miranda and A. Trejo and F. Salazar and L. A. P\'{e}rez and M. Cruz-Irisson},

url = {https://www.sciencedirect.com/science/article/pii/S2405829718313254},

doi = {https://doi.org/10.1016/j.ensm.2019.04.023},

issn = {2405-8297},

year  = {2019},

date = {2019-01-01},

journal = {Energy Storage Materials},

volume = {20},

pages = {438-445},

abstract = {The need for better energy-storage materials has attracted much attention to the development of Li-ion battery electrodes. Si nanowires have been considered as alternative electrodes, however the effects of Li on their electronic band gap and mechanical properties have been scarcely studied. In this work, a density functional study of the electronic and mechanical properties of hydrogen passivated silicon nanowires (H-SiNWs) grown along the [001] direction is presented. The Li atoms are gradually inserted at interstitial positions or replacing surface H atoms. The results show that, for surface-lithiated H-SiNWs, the semiconducting band gap decreases when the concentration of Li atoms increases; whereas the H-SiNWs become metallic even with the addition of only one interstitial Li atom. The formation energy diminishes with the concentration of Li atoms for surface-lithiated H-SiNWs, whereas the contrary behavior is found in the interstitial-lithiated H-SiNWs. Furthermore, for the surface-lithiation case, the Li binding energy reveals the existence of SiLi bonds, whereas for the interstitial-lithiation case, the Li binding energy increases when the Li grows up to a critical concentration, where some SiSi bonds break. Finally, for the case of surface-lithiation, the Young's modulus (Y) increases with the concentration of Li, whereas for the interstitial-lithiation case, Y suffers a sudden diminution at a certain Li concentration due to the large internal mechanical stresses within the nanowire structure. These results should be considered when regarding H-SiNWs as potential electrodes in Li-ion battery anodes.},

keywords = {electronic properties, Li batteries, Silicon nanowires, Young's modulus},

pubstate = {published},

tppubtype = {article}

}

@article{Gonz\'{a}lez-Mac\'{i}as2018,

title = {Theoretical study of the mechanical and electronic properties of [111]-Si nanowires with interstitial lithium},

author = {A. Gonz\'{a}lez-Mac\'{i}as and F. Salazar and A. Miranda and A. Trejo and I. J. Hern\'{a}ndez-Hern\'{a}ndez and L. A. P\'{e}rez and M Cruz-Irisson},

url = {https://doi.org/10.1007/s10854-018-9331-6},

doi = {10.1007/s10854-018-9331-6},

issn = {1573-482X},

year  = {2018},

date = {2018-09-01},

journal = {Journal of Materials Science: Materials in Electronics},

volume = {29},

number = {18},

pages = {15795-15800},

abstract = {In this work, we present a density functional study of the Young's modulus and electronic properties of hydrogen passivated silicon nanowires (H-SiNWs) grown along [111] crystallographic direction as function of concentration of interstitial lithium (Li) atoms. The study is performed using the supercell scheme, within the local density approximation implemented in the SIESTA code. The results show that the presence of Li closes the known semiconductor band gap of the H-SiNWs showing a like metallic behavior even when just one Li atom is placed in the nanowire structure. The participation of the Li atoms in the electronic density of states is almost constant in the valence and conduction bands. The formation energy analysis show how the system loses energetic stability when the concentration of Li grows, while the binding energy per Li atom suggests the formation of Si--Li bonds. On the other hand, the Young's modulus of the silicon nanowires (SiNWs) is higher than that of the H-SiNW and lower than the bulk value. Moreover, the Young's modulus is almost constant independently of the Li concentration. This result indicates that the H-SiNWs support the internal stress due to the addition of Li atoms and could offer a better useful life as electrodes in Li-ion batteries. The results of this work help to understand how the electronic and mechanical properties of H-SiNWs change during the charge/discharge process and the possibility to incorporate them as electrodes in Li batteries.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{deSantiago_2018,

title = {Carbon monoxide sensing properties of B-, Al- and Ga-doped Si nanowires},

author = {F Santiago and A Trejo and A Miranda and F Salazar and E Carvajal and L A P\'{e}rez and M Cruz-Irisson},

url = {https://dx.doi.org/10.1088/1361-6528/aab237},

doi = {10.1088/1361-6528/aab237},

year  = {2018},

date = {2018-03-01},

journal = {Nanotechnology},

volume = {29},

number = {20},

pages = {204001},

publisher = {IOP Publishing},

abstract = {Silicon nanowires (SiNWs) are considered as potential chemical sensors due to their large surface-to-volume ratio and their possible integration into arrays for nanotechnological applications. Detection of harmful gases like CO has been experimentally demonstrated, however, the influence of doping on the sensing capacity of SiNWs has not yet been reported. For this work, we theoretically studied the surface adsorption of a CO molecule on hydrogen-passivated SiNWs grown along the [111] crystallographic direction and compared it with the adsorption of other molecules such as NO, and O2. Three nanowire diameters and three dopant elements (B, Al and Ga) were considered, and calculations were done within the density functional theory framework. The results indicate that CO molecules are more strongly adsorbed on the doped SiNW than on the pristine SiNW. The following trend was observed for the CO adsorption energies: EA[B-doped] > EA[Al-doped] > EA[Ga-doped] > EA[undoped], for all diameters. The electronic charge transfers between the SiNWs and the adsorbed CO were estimated by using a Voronoi population analysis. The CO adsorbed onto the undoped SiNWs has an electron-acceptor character, while the CO adsorbed onto the B-, Al-, and Ga-doped SiNWs exhibits an electron-donor character. Comparing these results with the ones obtained for the NO and O2 adsorption, the larger CO adsorption energy on B-doped SiNWs indicates their good selectivity towards CO. These results suggest that SiNW-based sensors of toxic gases could represent a clear and advantageous application of nanotechnology in the improvement of human quality of life.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Gonz\'{a}lez-Mac\'{i}as_2018,

title = {Lithium effects on the mechanical and electronic properties of germanium nanowires},

author = {A Gonz\'{a}lez-Mac\'{i}as and F Salazar and A Miranda and A Trejo-Ba\~{n}os and L A P\'{e}rez and E Carvajal and M Cruz-Irisson},

url = {https://dx.doi.org/10.1088/1361-6528/aaaad4},

doi = {10.1088/1361-6528/aaaad4},

year  = {2018},

date = {2018-02-01},

journal = {Nanotechnology},

volume = {29},

number = {15},

pages = {154004},

publisher = {IOP Publishing},

abstract = {Semiconductor nanowire arrays promise rapid development of a new generation of lithium (Li) batteries because they can store more Li atoms than conventional crystals due to their large surface areas. During the charge\textendashdischarge process, the electrodes experience internal stresses that fatigue the material and limit the useful life of the battery. The theoretical study of electronic and mechanical properties of lithiated nanowire arrays allows the designing of electrode materials that could improve battery performance. In this work, we present a density functional theory study of the electronic band structure, formation energy, binding energy, and Young’s modulus (Y) of hydrogen passivated germanium nanowires (H\textendashGeNWs) grown along the [111] and [001] crystallographic directions with surface and interstitial Li atoms. The results show that the germanium nanowires (GeNWs) with surface Li atoms maintain their semiconducting behavior but their energy gap size decreases when the Li concentration grows. In contrast, the GeNWs can have semiconductor or metallic behavior depending on the concentration of the interstitial Li atoms. On the other hand, Y is an indicator of the structural changes that GeNWs suffer due to the concentration of Li atoms. For surface Li atoms, Y stays almost constant, whereas for interstitial Li atoms, the Y values indicate important structural changes in the GeNWs.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{https://doi.org/10.1002/qua.25713,

title = {Quantum confinement effects on the harmful-gas-sensing properties of silicon nanowires},

author = {Francisco Santiago and \'{A}lvaro Miranda and Alejandro Trejo and Fernando Salazar and Eliel Carvajal and Miguel Cruz-Irisson and Luis A. P\'{e}rez},

url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/qua.25713},

doi = {https://doi.org/10.1002/qua.25713},

year  = {2018},

date = {2018-01-01},

journal = {International Journal of Quantum Chemistry},

volume = {118},

number = {20},

pages = {e25713},

abstract = {Abstract In this work, the effects of the adsorption of different toxic gas molecules CO, NO, NO2, and SO2 on the electronic structure of hydrogen-passivated, [111]-oriented, silicon nanowires (H-SiNWs), are studied through density functional theory. To analyze the effects of quantum confinement, three nanowire diameters are considered. The results show that the adsorption energies are almost independent of the nanowire diameter with NO2 being the most strongly adsorbed molecule (∼3.44 eV). The electronic structure of small-diameter H-SiNWs is modified due to the creation of isolated defect-like states on molecule adsorption. However, these discrete levels are eventually hybridized with the former nanowire states as the nanowire diameter increases and quantum confinement effects become less evident. Hence, there is a range of small nanowire diameters with distinctive band gaps and adsorption energies for each molecule species.},

keywords = {Density Functional Theory, Nanowires, Sensors, silicon, toxic gases},

pubstate = {published},

tppubtype = {article}

}

@article{GONZALEZ2018420,

title = {Effects of surface and confinement on the optical vibrational modes and dielectric function of 3C porous silicon carbide: An ab-initio study},

author = {I. Gonz\'{a}lez and A. Trejo and M. Calvino and A. Miranda and F. Salazar and E. Carvajal and M. Cruz-Irisson},

url = {https://www.sciencedirect.com/science/article/pii/S0921452618303569},

doi = {https://doi.org/10.1016/j.physb.2018.05.024},

issn = {0921-4526},

year  = {2018},

date = {2018-01-01},

journal = {Physica B: Condensed Matter},

volume = {550},

pages = {420-427},

abstract = {Nanoporous silicon carbide is an interesting material with multiple potential applications, especially in supercapacitors, while there are many experimental investigations on the properties of this material, theoretical studies on its vibrational and optical properties are still scarce. This work studies the effect of quantum confinement on the dielectric function and optical vibrational modes of 3C porous silicon carbide from ab-initio calculations using density functional theory and density functional perturbation theory. The porous structures are modelled in the [001] direction by removing columns of atoms of a perfect Si crystal, obtaining two surface configurations: one with only C atoms and another one with Si atoms. Results show that the optical phonon modes of Si and C undergo a shift towards lower frequencies compared to their bulk counterparts due to phonon confinement effects. However, this shift is masked by H bending vibrations. Also, a surface H exchange process is observed on the Si-rich pore surface due to bond stretching and bending vibrations. The dielectric function analysis shows an increased optical activity in the porous cases due to a shift of the conduction band minimum towards gamma point for the C-rich case and high porosity Si-rich case, owing to quantum confinement effects. These results could be important for the applications of these nanostructures devices such as sensors and UV detectors.},

keywords = {DFPT, Dielectric function, Phonon optical modes, Porous silicon carbide},

pubstate = {published},

tppubtype = {article}

}

@article{Trejo2013,

title = {Ab-initio study of anisotropic and chemical surface modifications of $beta$-SiC nanowires},

author = {Alejandro Trejo and Jos\'{e} Luis Cuevas and Fernando Salazar and Eliel Carvajal and Miguel Cruz-Irisson},

url = {https://doi.org/10.1007/s00894-012-1605-y},

doi = {10.1007/s00894-012-1605-y},

issn = {0948-5023},

year  = {2013},

date = {2013-05-01},

journal = {Journal of Molecular Modeling},

volume = {19},

number = {5},

pages = {2043-2048},

abstract = {The electronic band structure and electronic density of states of cubic SiC nanowires (SiCNWs) in the directions [001], [111], and [112] were studied by means of Density Functional Theory (DFT) based on the generalized gradient approximation and the supercell technique. The surface dangling bonds were passivated using hydrogen (H) atoms and OH radicals in order to study the effects of this passivation on the electronic states of the SiCNWs. The calculations show a clear dependence of the electronic properties of the SiCNWs on the quantum confinement, orientation, and chemical passivation of the surface. In general, surface passivation with either H or OH radicals removes the dangling bond states from the band gap, and OH saturation appears to produce a smaller band gap than H passivation. An analysis of the atom-resolved density of states showed that there is substantial charge transfer between the Si and O atoms in the OH-terminated case, which reduces the band gap compared to the H-terminated case, in which charge transfer mainly occurs between the Si and C atoms.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}