As opposed to the standard graphite anode used for lithium (Li) ion batteries (LIBs), a material sodium (Na) (NIBs) has not yet been reported. Black phosphorus is potentially very attractive as an NIBs, it layered structure similar but greater interlayer distance. In this work, we propose atomistic mechanism sodiation of black phosphorus, based on first-principles calculations. The maintained up composition Na0.25P, with one-dimensional (an intercalation process) occurring in spaces...

We report a density functional theory (DFT) study regarding the effects of atomic defects, such as vacancies and adatom adsorption, on electronic magnetic properties phosphorene (a two-dimensional monolayer black phosphorus). A monovacancy in creates an in-gap state band gap pristine induces moment, even though is nonmagnetic. In contrast, both planar staggered divacancies do not change phosphorene, although divacancy states gap. Our DFT calculations also show that adsorption nonmetallic...

Tungsten–nitrogen (W–N) codoping has been known to enhance the photocatalytic activity of anatase TiO2 nanoparticles by utilizing visible light. The doping effects are, however, largely dependent on calcination or annealing conditions, and thus, massive production quality-controlled photocatalysts still remains a challenge. Using density functional theory (DFT) thermodynamics time-dependent DFT computations (TDDFT), we investigate atomic structures N W–N in TiO2, as well effect thermal...

In this study, ZnS/ethylenediamine nanosheets were obtained by solvothermal synthesis and modified into composites of ZnS ZnO heat treatment. Compared to pure ZnS, the ZnS/ZnO composite showed superior photocatalytic activity towards hydrogen evolution from water (500 µmol h−1 g−1) photoreduction toxic Cr(VI) (k = 0.0078 min−1). Rietveld refined XRD patterns, high resolution-transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), UV–vis diffuse reflectance spectra...

We investigate the effect of nitrogen and boron doping on Li diffusion through defected graphene using first principles based density functional theory. While a high energy barrier rules out possibility Li- pristine graphene, reduces with incorporation defects. Among most common defects in divacancy encounters lowest 1.34 eV. The doped defected-graphene sheets has been studied. N-doping monovacancy significantly. increasing number N atoms. On other hand, for divacancy, binds plane sheet, an...

Metal-free carbon materials are attractive Pt-based catalyst alternatives. However, despite efforts, the reaction mechanism remains elusive. Thus, we investigated role of defects (dopant nitrogen and vacancy) on catalytic oxygen reduction in a metal-free material focusing effect structural flexibility. Crucially, lower energy barrier for sp2/sp3 transition carbon-centered O2-adsorption sites by releasing strain during reaction. In particular, low-coordinated pyridinic-N displaces from plane...

In addition to composition, the structure of a catalyst is another fundamental determinant its catalytic reactivity. Recently, anomalous Ti oxide-rich surface phases ternary oxides have been stabilized as nonstoichiometric epitaxial overlayers. These structures give rise different modes oxygen binding, which may lead oxidative chemistry. Through density functional theory investigations and electrochemical measurements, we predict subsequently show that such TiO2 double-layer reconstruction...

The photoluminescence intensity of Bi-doped Y₂O₃ is increased in a high oxygen partial pressure atmosphere due to the healed vacancy.

Recent studies on crystal facet manipulation of anatase ${\text{TiO}}_{2}$ in photocatalysis have revealed that reduction and oxidation reactions preferably occur (100)/(101) (001) facets, respectively; however, a fundamental understanding their origin is lacking. Here, as result first-principles calculations, we suggest dissimilar trend the anisotropy electron vs hole bulk transport can be dominant underlying mechanism for difference photochemical activity. Photoexcited electrons holes are...

The visible-light absorption and luminescence of wide band gap (3.25 eV) strontium titanate (SrTiO3) are well-known, in many cases, to originate from the existence natural oxygen deficiency material. In this study based on density functional theory (DFT) calculations, we provide, best our knowledge, first report indicating that vacancies bulk surfaces SrTiO3 (STO) play different roles optical magnetic properties. We found doubly charged state vacancy (VO(2+)) is dominant does not contribute...

To enhance the photoluminescence of lanthanide oxide, a clear understanding its defect chemistry is necessary. In particular, when yttrium widely used phosphor, undergoes doping, several atomic structures may be coupled with point defects that are difficult to understand through experimental results alone. Here, we report strong enhancement (PL) Y2O3:Bi3+ via codoping Li+ ions and suggest plausible mechanism for using both computational studies. The into phosphor was found cause significant...

The composition and reconstruction of oxide surfaces can be deterministically controlled via ambient conditions. We demonstrate that such intrinsic alterations have a crucial effect on the surface dipole reactivity, even for with same crystallographic plane. potential drops ${\mathrm{BaTiO}}_{3},\phantom{\rule{0.16em}{0ex}}{\mathrm{SrTiO}}_{3},\phantom{\rule{0.16em}{0ex}}{\mathrm{LaFeO}}_{3}$, ${\mathrm{TiO}}_{2}$ various reconstructions compositions are shown to vary by as much 5 V, leading...

Abstract Sb atoms in In 3 SbTe 2 (IST) are partially substituted by 3.2–5.5 at.% of Bi atoms. As a result, the NaCl crystal structure IST is slightly distorted. The distorted inter-planar angles observed with fast Fourier transformation lattice images within maximum range interplanar calculated density functional theory. When content increased, crystallization temperature becomes relatively lower than that IST, activation energy decreases from 5.29 to 2.61 eV and specific heat melting point...

Li4Ti5O12 (LTO) has attracted tremendous attention as a stationary Li-ion battery anode material due to its excellent stability. However, the poor rate capability caused by low electrical conductivity limits practical use. Previously, Mg-doping in LTO been used improve and electrochemical properties, but Mg-doped system generally exhibits large anomalies properties capacities, which reliable mass-production of engineered LTO. In this study, on basis first-principles calculations related...

This study established a dynamic Z-scheme driven heterostructure of ZnO-ZnS (ZnOS) nanoparticles (NPs) by sulfidation ZnO NPs. The ZnOS composites with different atomic ratios S/O were analyzed multiple characterization techniques. composite materials ratio 1:1 yielded the best photocatalytic results for toxic Cr(VI) removal from water and H2 production under UV light. examined energy transfer behavior at junction first time via electronic structure modeling using density functional theory...

The competition between mixing energy and surface determines atomic pattern of bimetallic nanoparticles.

We present a low temperature and solution-based fabrication process for reduced graphene oxide (rGO) electrodes electric double layer capacitors (EDLCs). Through the heat treatment at 180 °C between spin coatings of (GO) solution, an electrode with loosely stacked GO sheets could be obtained, base coating was partially reduced. The thickness freely controlled as these were prepared without additive spacer. layers then fully to rGO relatively 300 under ambient atmospheric conditions, not in...

We show, using density functional theory (DFT) calculations, that the Schottky barrier height (SBH) at PtSi/Si interface can be lowered by uniaxial strain applied not only on Si but also PtSi. The was to (001) direction of and PtSi, which is normal for interface. SBH hole 0.08 eV under 2% tensile 0.09 4 % compressive Because contact approximately 0.2 eV, this amount reduction significantly lower resistance contact; thus applying both PtSi possibly enhances performance field effect...

We investigate the structural, mechanical, and electronic properties of graphite-like amorphous carbon coating on bulky silicon to examine whether it can improve durability anodes lithium-ion batteries using molecular dynamics simulations ab-initio structure calculations. Structural models are constructed atomic deposition with low incident energies (1–16 eV). As energy decreases, ratio sp2 carbons increases, that sp3 films become more porous. The prepared very contain conducting channels....