A nanosilver-actuated high-performance porous silicon anode from recycling of silicon waste

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 use DWSSP for increased sustainability and protection of the environment. Here, nanoporous silicon (PSi) 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 nanocopper-assisted etching. Next, porous PSi/Ag composites were prepared by nanosilver-assisted etching, using dopamine as a source of organic for surface coating. Carbon-coated PSi/Ag nanocomposites (PSi/Ag/C) exhibited excellent cycling performance with a 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.