Silicon particles confined in carbon nanotubes anode materials by green utilization of carbon dioxide in lithium-ion battery

Silicon anodes are important candidates for high energy lithium-ion batteries (LIBs) because of their large theoretical specific capacity. However, silicon usually undergoes severe volume changes (300-400 %) in the lithiation/delithiation process, resulting in low Coulombic efficiency (CE) and rapid capacity decay. Herein, the nanotube shaped silicon-carbon composite has been designed by using a simple dealloying method in greenhouse gas (CO2) environment. Encouragingly, the tubular structured composite prepared at 1.5 h shows best electrochemical performance as anodes for LIBs among the three samples. The first specific discharge capacity could reach 2302.5 mA h g-1 when cycled at 0.2 A g-1, corresponding an initial CE of 70 %. Along with the increasing number of cycles, the composite exhibits high Coulombic efficiency compared to commercial Si particles. The material also displays excellent rate capacity and stability with a high specific capacity of 714.6 mA h g-1 at 5 Ag-1. In situ differential electrochemical mass spectrometry is further used to analyze the phenomenon of gas generation during the formation of solid electrolyte interface layer. In addition, the fabricated Si/LiNi0.3- Co0.3Mn03O2 full battery demonstrates high initial specific capacity up to 171 mA h g- 1 as well as moderate cycling stability for 50 cycles.