Electrochemical behavior of Ag nanoparticle-incorporated Li4Ti5O12 nanofibers as Li-ion battery anodes under visible light exposure

Abstract

To gain insight into the light-induced plasmonic effect on metal nanoparticle-doped Li4Ti5O12 nanofibers (LTO NFs), we used Ag-LTO NFs as an anode material for solar Li-ion battery-based coin cells. The efficient incorporation of silver nanoparticles into LTO NFs improved electrochemical performance by shortening the electronic pathway and increasing conductivity in the presence of light. To better understand this process, in situ electrochemical studies were performed using a perforated coin cell with its anode subjected to light exposure. The studies revealed a synergistic effect of light and Ag-LTO NFs that led to both light-induced and electrochemical Li+ insertion, which in turn resulted in an enhanced Li-extraction and insertion speed. Overall, better reversibility and a 1.5-fold improvement in the conductivity of the Ag-LTO NFs under light irradiation were achieved. Our work opens an avenue for promising light-responsive plasmonic heterojunction materials toward a sustainable response to the increasing demand for high-power energy storage.