Scalable Approach to Multi-Dimensional Bulk Silicon-Based Anodes Via Catalytic Etching and Growing

Bulk silicon-based materials including silicon, silicon mono-oxide have high specific capacity and are more suitable for practical uses in the industry, although nano-sized silicon materials show superior cell performance due to their small volume change and low diffusion length. Here, we demonstrate simple ways to make multi-dimensional silicon-based materials by utilizing commercially available bulk silicon and silicon mono-oxide, through catalytic etching or catalytic growing methods. These materials showed highly improved reversible capacity > 2000mAh/g in a bulk silicon and > 1400mAh/g in a bulk silicon mono-oxide, and stable cycle performance compared to bare bulk powders. These catalytic etching and growing routes are simple, low cost and mass producible, thus provide an effective method for high performance anode materials.