High-performance red phosphorus/carbon nanofibers/graphene free-standing paper anode for sodium ion batteries†
Red phosphorus (P) has been regarded as an attractive anode material in a sodium-ion battery (SIB) due to its natural abundance and higher theoretical specific capacity. We developed a novel flexible P/carbon nanofibers@reduced graphene oxide (P/CFs@RGO) electrode for sodium-ion batteries through simple vapor-redistribution and electrospinning. In this multi-layer structured P/CFs@RGO electrode, the large volume changes of the red P layer during cycling can be easily buffered and the loss of P from carbon fibers is prevented. In addition, the electrodes have better electron transport. As the result, the as-prepared P/CFs@RGO electrode delivers a high capacity retention of 725.9 mA h g−1 after 55 cycles at 50 mA g−1 and a significant capacity of 406.6 mA h g−1 even at large current densities of 1000 mA g−1 after 180 cycles.