Forcespun and Coated SnO2/TiO2/C Composite Fibers as Anode Materials for Sodium Ion Batteries

Abstract

Sodium-ion batteries (SIBs) are being demanded over the years due to profusion of Na in nature as well as the unavailability, expensiveness, and fragility of rechargeable Li-ion batteries (LIBs). Metal-oxide anode materials face various pitfalls such as volume expansion during charge/discharge cycles, high irreversible capacity, and conductivity-related issues. Porous structures aligned with amorphous carbon into the metal oxide is a novel technique that has been used to synthesize novel nanostructures for SIBs. Tin oxide has been recently used as a good anode material for SIBs, but SnO2 suffers from high volume change and low capacity retention after prolonged charge/discharge cycles. SnO2 coupled with Titanium oxide, has been proven as a good anode material due its good capacity retention and improved electrochemical performance and cyclability. The current work focuses on the processing of centrifugally spun PAN/PMMA/SnO2/TiO2 composite precursor fibers to fabricate SnO2/SnO2/C composite fibers for SIBs as anode materials in LIBs and SIBs. The electrochemical performance of the composite fibers was evaluated by galvanostatic charge/discharge, cyclic voltammetry (CV) and rate performance experiments. The SnO2/TiO2/C composite-fiber anode showed improved electrochemical performance when compared to SnO2/TiO2 composite fibers which was attributed to the synergetic effect of TiO2.