Reducing the SiOx layer on Si/reduced graphene oxide enables fast and reversible lithium-ion storage capability for lithium-ion batteries

Abstract

To investigate whether the presence of a SiOx layer affects the electrochemical performance of silicon-based materials, particularly the silicon-carbon anode material, a facile and scalable process involving HCl etching, annealing, and HF etching was employed to synthesize a silicon-carbon composite (Si/SiOx-rGO) and reduce the SiOx layer content at the silicon-carbon interface to obtain a Si-rGO composite. Experimental results demonstrate that this method effectively reduces the SiOx content in the composite. By decreasing the SiOx layer content, the Si-rGO composite exhibits the specific capacities of 758.3 mAh g−1 at 3 A g−1 and 557 mAh g−1 at 5 A g−1. After 200 cycles at 2 A g−1, it still retains a capacity of 930.8 mAh g−1. These findings offer comprehensive insights into the SiOx layer at the silicon-carbon interface, thereby enhancing the application of silicon-based anode materials.