Ag‐doped hollow ZIFs‐derived Si@C composite based on waste silicon for lithium‐ion battery anodes

Abstract Currently, silicon is considered one of the most competitive candidates for the anode materials of lithium‐ion batteries (LIBs), mainly benefiting from its extremely superior theoretical capacity. However, their industry application usually suffers from the expensive nano silicon. In the present study, the kerf loss silicon (KL Si) waste generated during the production of silicon wafers in photovoltaic industry is utilized as a low‐cost nano silicon after pre‐treatment. An Ag‐doped hollow zeolitic imidazolate framework‐8–derived Si@C composite (Si@HZIF‐C/Ag) is synthesized via an in situ tannic acid etching/reduction method. The advanced structure effectively enhances the electrical conductivity and mitigates the volume fluctuation of silicon during charge/discharge process; it also facilitates the transport of Li + due to the rich pore structure, thus resulting in an excellent electrochemical performance. The tested results indicate that the discharge capacity of Si@HZIF‐C/Ag electrodes is up to 900.0 mAh g −1 after 300 cycles under 0.1 A g −1 . Moreover, the discharge specific capacity remains at 400.2 mAh g −1 after 500 cycles under 0.25 A g −1 , and the electrode exhibits good rate performance with a capacity retention of 99.2% across 0.1–1 A g −1 . The presented route for silicon‐based anode with promoted lithium storage performance shows huge potential for industry application in new‐generation LIBs.