ES22-Gurmesa

Author: Gurmesa, Gamachis - Addis Ababa University, Ethiopia.

Title: Rational design of biaxial strain on the electronic and ionic conductivity of Na2MnSiO4 cathode material for Rechargeable Sodium-ion batteries

Abstract: Using first-principles calculations, biaxial tensile ((e = 2 and 4%) and compressive (e = -2 and -4%) straining of Na2MnSiO4 lattices resulted in the radial distances cut off 1.65 and 2 Å, respectively, in the first and second nearest neighbors shell from the center. The Si-O and Mn-O bonds with prominent probability density peaks validated structural stability. Wide-band gap of 2.35 (e = 0%) and 2.54 eV (e = -4%), and narrow bandgap of 2.24 eV (e = +4%) estimated with stronger coupling of p-d 휎 bond than that of the p-d 휋 bond, mainly contributed from oxygen p-state and manganese d-state. Na+ - ion diffusivity is enhanced by three orders of magnitude as applied biaxial strain changes from compressive to tensile. According to the findings, the rational design of biaxial strain would improve the ionic and electronic conductivity of Na2MnSiO4 cathode material for advanced rechargeable Sodium-ion batteries.

Other authors:
Yedilfana Mekonnen, Addis Ababa University Chernet Geffe, Addis Ababa University Tamiru Teshome, Addis Ababa University