High-value recycling of silicon sawing/cutting waste into stable silicon/carbon anodes via integrated strategy

With the rapid development of the photovoltaic and solar cell industry, the growing generation of crystalline silicon sawing/cutting waste has become an urgent problem. However, silicon (Si) is considered a promising alternative to graphite for next-generation high-energy density Li-ion batteries owing to its much higher theoretical capacity. Herein, photovoltaic silicon sawing/cutting waste is recycled as high-performance silicon/carbon anode active material of lithium-ion battery through an integrated strategy combining mechanical activation, acid leaching, dopamine self-assembly coating, and graphite buffering. The as-prepared silicon/carbon composite features a hierarchical architecture, which is composed of nanometer-sized Si particles covered with amorphous carbon and uniformly anchored in a conductive carbon matrix, effectively mitigating the severe volume fluctuation during charge/discharge. Enabled by the enhanced structural stability and interfacial compatibility, the activated silicon/carbon anode delivers a high reversible capacity of 641 mAh g −1 after 350 cycles at 0.5 A g −1 , with a capacity retention of 98.1%. Therefore, the investigation introduces an innovative method for recycling and enhancing the value of photovoltaic silicon sawing/cutting waste for further use, offering a sustainable and economically viable solution.