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

J. JUAN; P. BECHTHOLD; F. ESCUDERO; F. GAZTAÑAGA; P. V. JASEN; R. FACCIO; E. A. GONZÁLEZ

Workshop; 7th International Workshop on Lithium, Industrial Minerals and Energy ? IWLiME2020; 2020

Li adsorption onto pristine and defective siliceneis still not fully understood because of the lack of reliable experimentalmethods to make freestanding silicene so far. First-principle modeling is apowerful tool for battery research as it can accurately study the structuraland electronic properties of electrode and electrolyte materials as well as theinteractions between different materials.The aim of this work is to analyzethe interaction of Li0 (Li atom), Li-ion (Li+) andcharged Li (Li-) with pristine silicene single-layer and compare theperformance among them. Herein we use First-principles calculations to studythe adsorption and mobility of Li adatoms on a silicene sheet, using VASP code[1-3]. We analyze the changes in the electronic structure, the diffusion of theLi adatoms using the Nudged Elastic Band method (NEB) [4-5] and the chargedensity distribution through charge density difference diagrams in all cases.In addition, we calculate the quantum capacity (QC) and the average opencircuit voltages (OCV). Our results show that the singlevacancy generates new states in the Fermi level, which enhances the quantumcapacity in positive biases (see Figure 1). This fact makes this a promisingcandidate for application as supercapacitors electrodes. When Li adsorption isconsidered, we found that Li+ is the most stable case. The lowest diffusionbarrier for the pristine case is Li+. Acknowledgments: Our work was supported by ANPCyTthrough PICT 2016 Raíces N°2016-4085 Res. N° 285/16, PICT 2016 N°2016-4094 Res. N°285/16 and PIP-CONICET 2014-2016 code: 11220130100436CO research grants, aswell as by SGCyT-UNS. EAG, PVJ and PB are members of IFISUR-CONICET. JJ, FE,FG, are fellow researchers at this institution. RF acknowledges PEDECIBA,CSIC-UdelaR and ANII, all Uruguayan Institutions for financial support. References:  [1] G. Kresse, J. Hafner, Ab initiomolecular dynamics for liquid metals, Phys. Rev. B 47 (1993) 558?561. [2] G. Kresse, J. Furthmüller,Efficient iterative schemes for ab initio total-energy calculations using aplane-wave basis set, Phys. Rev. B 54 (1996) 11169?11186. [3] G. Kresse, J. Furthmüller,Efficiency of ab-initio total energy calculations for metals and semiconductorsusing a plane-wave basis set, Comput. Mater. Sci. 6 (1996) 15?50. [4] G. Henkelman, H. Jónsson, Improved tangent estimate in the nudgedelastic band method for finding minimum energy paths and saddle points, J. Chem. Phys. 113 (2000) 9978?9985. [5] G. Henkelman, H. Jónsson, A climbing imagenudged elastic band method for finding saddle points and minimum energy paths, J. Chem. Phys. 113 (2000) 9901?9904.<!-- /* Font Definitions */ @font-face{font-family:"Cambria Math";panose-1:2 4 5 3 5 4 6 3 2 4;mso-font-charset:0;mso-generic-font-family:roman;mso-font-pitch:variable;mso-font-signature:-536870145 1107305727 0 0 415 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:swiss;mso-font-pitch:variable;mso-font-signature:-536859905 -1073732485 9 0 511 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",sans-serif;mso-fareast-font-family:Calibri;}.MsoChpDefault{mso-style-type:export-only;mso-default-props:yes;font-family:"Calibri",sans-serif;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 72.0pt 72.0pt 72.0pt;mso-header-margin:36.0pt;mso-footer-margin:36.0pt;mso-paper-source:0;}div.WordSection1{page:WordSection1;}<!-- /* Font Definitions */ @font-face{font-family:"Cambria Math";panose-1:2 4 5 3 5 4 6 3 2 4;mso-font-charset:0;mso-generic-font-family:roman;mso-font-pitch:variable;mso-font-signature:-536870145 1107305727 0 0 415 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:swiss;mso-font-pitch:variable;mso-font-signature:-536859905 -1073732485 9 0 511 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",sans-serif;mso-fareast-font-family:Calibri;}.MsoChpDefault{mso-style-type:export-only;mso-default-props:yes;font-family:"Calibri",sans-serif;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 72.0pt 72.0pt 72.0pt;mso-header-margin:36.0pt;mso-footer-margin:36.0pt;mso-paper-source:0;}div.WordSection1{page:WordSection1;}