Nano-silver Actuated High-performance Porous Silicon Anode from Recycling of Silicon Waste

Abstract The global need for improved fuels has promoted the development of the renewable photovoltaic industry. However, a significant amount of diamond wire saw silicon powder (DWSSP, ∼300,000 t/a) is produced during the process of solar cell manufacturing. Thus, there is a significant need for strategies to recycle and utilize DWSSP for increased sustainability and protection of the environment. Here, nano-porous silicon composites materials derived from silicon cutting waste were used to fabricate lithium-ion anodes with high capacity and stable cycling performance. DWSSP was chemically crushed using nano-copper-assisted etching. Next, porous silicon/Ag composites (PSi/Ag) were prepared by nano-silver-assisted etching, using dopamine as a source of organic for surface coating. Carbon-coated porous silicon/Ag nanocomposites (PSi/Ag/C) exhibited excellent cycling performance with retained discharge capacity of 1092.9 mAh g-1 after 300 cycles at 1000 mA/g, with a capacity retention rate of 80%. These results indicate that PSi/Ag/C from DWSSP can be used to prepare functional lithium-ion battery anodes. This work describes the high-value utilization of an abundant waste material produced in the solar industry and provides an effective strategy to produce porous materials for energy storage.