Charged Lithium adsorption and diffusion on pristine and defective silicene as electrode material candidate: A DFT study

F. ESCUDERO; R. FACCIO; P. BECHTHOLD; P. JASEN; J. JUAN; F. GAZTAÑAGA; E. GONZALEZ

Antofagasta

Workshop; 7th International Workshop on Lithium, Industrial Mineral and Energy; 2020

Liadsorption onto pristine and defective silicene is still not fully understoodbecause of the lack of reliable experimental methods to make freestandingsilicene so far. First-principle modeling is a powerful tool for batteryresearch as it can accurately study the structural and electronic properties ofelectrode and electrolyte materials as well as the interactions betweendifferent materials. Theaim of this work is to analyze the interaction of Li0 (Li atom),Li-ion (Li+) and charged Li (Li-) with pristine silicenesingle-layer and compare the performance among them. Herein we useFirst-principles calculations to study the adsorption and mobility of Liadatoms on a silicene sheet, using VASP code [1-3]. We analyze the changes inthe electronic structure, the diffusion of the Li adatoms using the NudgedElastic Band method (NEB) [4-5] and the charge density distribution throughcharge density difference diagrams in all cases. In addition, we calculate thequantum capacity (QC) and the average open circuit voltages (OCV). Our results show thatthe single vacancy generates new states in the Fermi level, which enhances thequantum capacity in positive biases (see Figure 1). This fact makes this apromising candidate for application as supercapacitors electrodes. When Liadsorption is considered, we found that Li+ is the most stable case. The lowestdiffusion barrier for the pristine case is Li+.<!-- /* Font Definitions */@font-face{font-family:"Cambria Math";panose-1:2 4 5 3 5 4 6 3 2 4;mso-font-charset:1;mso-generic-font-family:roman;mso-font-format:other;mso-font-pitch:variable;mso-font-signature:0 0 0 0 0 0;}@font-face{font-family:Calibri;panose-1:2 15 5 2 2 2 4 3 2 4;mso-font-charset:0;mso-generic-font-family:auto;mso-font-pitch:variable;mso-font-signature:3 0 0 0 1 0;} /* Style Definitions */p.MsoNormal, li.MsoNormal, div.MsoNormal{mso-style-unhide:no;mso-style-qformat:yes;mso-style-parent:"";margin:0cm;margin-bottom:.0001pt;mso-pagination:widow-orphan;font-size:12.0pt;font-family:Calibri;mso-fareast-font-family:Calibri;mso-bidi-font-family:Calibri;}.MsoChpDefault{mso-style-type:export-only;mso-default-props:yes;font-family:Calibri;mso-ascii-font-family:Calibri;mso-fareast-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:Calibri;}size:612.0pt 792.0pt;margin:72.0pt 90.0pt 72.0pt 90.0pt;mso-header-margin:36.0pt;mso-footer-margin:36.0pt;mso-paper-source:0;}div.WordSection1{page:WordSection1;}<!-- /* Font Definitions */@font-face{font-family:Calibri;panose-1:2 15 5 2 2 2 4 3 2 4;mso-font-charset:0;mso-generic-font-family:auto;mso-font-pitch:variable;mso-font-signature:3 0 0 0 1 0;} /* Style Definitions */p.MsoNormal, li.MsoNormal, div.MsoNormal{mso-style-unhide:no;mso-style-qformat:yes;mso-style-parent:"";margin:0cm;margin-bottom:.0001pt;mso-pagination:widow-orphan;font-size:12.0pt;font-family:Calibri;mso-fareast-font-family:Calibri;mso-bidi-font-family:Calibri;}.MsoChpDefault{mso-style-type:export-only;mso-default-props:yes;font-family:Calibri;mso-ascii-font-family:Calibri;mso-fareast-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:Calibri;}size:612.0pt 792.0pt;margin:72.0pt 90.0pt 72.0pt 90.0pt;mso-header-margin:36.0pt;mso-footer-margin:36.0pt;mso-paper-source:0;}div.WordSection1{page:WordSection1;}