Upcycling of Electroplating Sludge into Ultrafine Sn@C Nanorods with Highly Stable Lithium Storage Performance

Sn-based anode materials have become potential substitutes for commercial graphite anode due to their high specific capacity and good safety. In this paper, ultrafine Sn nanoparticles embedded in nitrogen and phosphorus codoped porous carbon nanorods (Sn@C) are obtained by carbonizing bacteria that adsorb the Sn electroplating sludge extracting solution. The as-prepared Sn@C rod-shaped composite exhibits superior electrochemical Li-storage performances, such as a reversible capacity of approximate 560 mAh/g at 1 A/g and an ultralong cycle life exceeding 1500 cycles, with approximately no capacity decay. The ultrastable structure of the Sn@C was revealed using in situ transmission electron microscope at the nanoscale and indicated that the Sn@C composite could restrict the volume expansion of Sn nanoparticles during the lithiation/delithiation cycles. This work provides a new insight into addressing the electroplating sludge and designing novel lithium ion battery anodes.