A simple and scalable approach to hollow silicon nanotube (h-SiNT) anode architectures of superior electrochemical stability and reversible capacity

Abstract

Strain engineered unique architectures of silicon nanotubes have garnered tremendous attention as high capacity and stable lithium-ion battery (LIB) anodes. However, the expensive nature of the hitherto synthesis techniques used to produce the silicon nanotubes combined with the inferior yield and poor loading densities have rendered these unique morphologies unattractive for commercial LIB systems. In this study, we report for the first time, a simple, facile, and more importantly, recyclable sacrificial template based approach involving magnesium oxide (MgO) nanorods for producing scalable quantities of hollow silicon nanotubes (h-SiNTs) architectures. Electrodes fabricated from these h-SiNTs derived from this novel scalable approach exhibit equitable loadings and reversible capacities in excess of 1000 mA h g⁻¹ at a high current density of 2 A g⁻¹ for nearly 400 cycles, combined with a very low fade rate of only 0.067% loss per cycle. The high capacity, good current rate characteristics combined with excellent charge-transfer kinetics as well as the long cycle life of these engineered h-SiNTs render this approach viable for industry scale while also boding promise for practical applications.