arXiv subjects

Amreen Bano

Publications and source records attributed to Amreen Bano.

3 recordsLinked to original sources

arXiv2024

Atomistic Modelling of High-Entropy Layered Anodes and Their Electrolyte Interface

Van der Waals (vdW) heterostructures have attracted intense interest worldwide as they offer several routes to design materials with novel features and wide-ranging applications. Unfortunately, at present, vdW heterostructures are restricted to a small number of stackable layers, due to the weak vdW forces holding adjacent layers together. In this work, we report on computational studies of a bulk vdW material consisting of alternating TiS2 and TiSe2 (TSS) vertically arranged layers as a potential candidate for anode applications. We use density functional theory (DFT) calculations and ab-initio molecular dynamics (AIMD) simulations to explore the effect of high entropy on several electrochemically relevant properties of the bulk heterostructure (TSS-HS) by substituting Mo6+ and Al3+ at the transition metal site (Ti4+). We also study the solvation shell formation at the electrode-electrolyte interface (EEI) using AIMD to determine Li-coordination. Based on the properties computed using DFT and AIMD we propose that high entropy TSS-HS (TSS-HE) might possess improved electrochemical performance over standard TSS-HS. Factors that could improve the performance of TSS-HE are 1) Less structural deformation, 2) Strong bonding (Metal-Oxygen), 3) Better electron mobility, 4) Wider operational voltage window, and 5) Faster Li-ion diffusion. Our observations suggest that 'high entropy' can be an effective strategy to design new anode materials for improving electrochemical performance of Li-ion batteries.

physics.comp-ph↗

arXiv2022

Coexistence of Rashba Effect and Spin-valley Coupling in TiX2 (X= Te, S and Se) based Heterostructures

Spin-orbit coupling (SOC) combined with broken inversion symmetry play key roles in inducing Rashba effect. The combined spontaneous polarization and Rashba effect enable controlling a material's spin degrees of freedom electrically. In this work we investigated the electronic band structure for several combinations of TiX2 monolayers (X= Te, S and Se): TiTe2/TiSe2, TiTe2/TiS2, and TiSe2/TiS2. Based on the observed orbital hybridization between the different monolayers in these hetero-structures (HSs), we conclude that the most significant Rashba splitting occurs in TiSe2/TiS2. Subsequently, we used Fluorine (F) as an adatom over the surface of TiSe2/TiS2 at hollow and top sites of the surface to enhance the Rashba intensity, as the F adatom induces polarization due to difference in charge distribution. Furthermore, by increasing the number of F atoms on the surface, we reinforced the band splitting, i.e., we observe Rashba splitting accompanied by Zeeman splitting at the valence-band edge states. Berry curvatures at K and K' with equal and opposite nature confirms the existence of valley polarization. The computationally observed properties suggest that these HSs are promising candidates for spin-valley Hall effect devices and other spintronic applications.

cond-mat.mtrl-sci↗

arXiv2019

$CrI_{3}$-$WTe_{2}$: A Novel Two-Dimensional Heterostructure as Multisensor for $BrF_3$ and $COCl_2$ Toxic Gases

A new multisensor (i.e. resistive and magnetic) $CrI_{3}$-$WTe_{2}$ heterostructure (HS) to detect the toxic gases $BrF_3$ and $COCl_2$ (Phosgene) has been theoretically studied in our present investigation. The HS has demonstrated sensitivity towards both the gases by varying its electronic and magnetic properties when gas molecule interacts with the HS. Fast recovery time ($< 0.14 fs$) under UV radiation has been observed. We have considered two configurations of $BrF_3$ adsorbed HS; 1) when F ion interacts with HS (C1) and 2) when Br ion interacts with HS (C2). In C1 case the adsorption energy $E_{ad}$ is observed to be -0.66 eV while in C2 it is -0.95 eV. On the other hand in case of $COCl_2$ $E_{ad}$ is found to be -0.42 eV. Magnetic moments of atoms are also found to vary upon gas adsorption indicates the suitability of the HS as a magnetic gas sensor. Our observations suggests the suitability of $CrI_{3}$-$WTe_{2}$ HS to respond detection of the toxic gases like $BrF_3$ and $COCl_2$.

cond-mat.mtrl-sci↗