Three-dimensional porous copper framework supported group IVA element materials as sodium-ion battery anode materials

Sodium-ion batteries have been proposed as a potential complement to existing lithium-ion batteries. Due to the difference between Na and Li in nature, the group IVA element (Si, Ge, Sn)-based anodes, which are attractive for Li-ion batteries, have not been widely utilized for Na-ion batteries. In this study, the sodium storage properties of Si, Ge and Sn are investigated using 3D porous copper framework as current collector. The optimized porous Cu-Ge electrode displays enhanced cycling stability and rate capabilities by reason of its favorable 3D porous structures and the conductive network of Cu scaffold. The stable cycling performance of 3D porous Sn anode further demonstrates the advantages of the interconnected porous configuration of the electrodes. The sodium-ion insertion behaviors of amorphous silicon are experimentally studied and reported. The successful configuration of these group IVA element-based anodes can provide insight into exploring and designing new Na-ion electrode materials.