Na–Ge glass anode network mixed with bismuth oxide nanocrystallites: A high capacity anode material for use in advanced sodium-ion battery design

Abstract

Exploring the growing phenomenon of amorphous intermediate domains at nanoscale and its application as flexible active centres in a glass anode network is decisively significant to enhance sodium-ion battery performance. The outstanding stability of nanosized h-Na3Bi and NaGe domains in the glass anode network makes it more electrochemically efficient and increases its ionic conductivity. Subsequently, improved cycle stability and rate capability of glass anode half-cell have been achieved due to optimum void space between domains and open glass network. It also exhibits enhanced ability to withstand extensive volume variations during the repetitive sodiation/de-sodiation process. The size of the amorphous intermediate domains, structure, and lattice planes separation has been estimated based on the HRTEM and SAED images. The advantages gained by the growth of amorphous domains in the sodium-germanate glass network highlights its potential application as high-performance anode components for the advancement of Na-ion battery (NIB) efficiency.