Light-assisted synthesis of copper/cuprous oxide reinforced nanoporous silicon microspheres with boosted anode performance for lithium-ion batteries

Abstract

Silicon is generally accepted as an outstanding anode material to promote the use of high-capacity lithium-ion batteries (LIBs). Herein, novel Cu/Cu2O reinforced nanoporous silicon microspheres are successfully constructed by a simple photodeposition-galvanic replacement method. The reduction reactions driven by photogenerated electrons and galvanic replacement jointly promote the in-situ deposition of Cu/Cu2O on porous silicon microspheres. Compared with the as-constructed anode materials in the absence of illumination, the composites obtained with the light irradiation display better electrochemical performance. The ratio of Si and Cu in the final products can be effectively adjusted by modulating the concentration of Cu2+ in the reaction solutions. Benefiting from the enhanced structure stability and excellent electronic conductivity, the final optimized product exhibits superior Li-storage performance, delivering a reversible capacity of 1240.1 mAh g−1 after 200 cycles at a high current of 1 A g−1. It is worth mentioning that the as-constructed light-assisted method provides an efficient and universal pathway to tailor and synthesize other superior Si based anode materials.