Recent developments of phosphorus-based anodes for sodium ion batteries

Phosphorus (P) is one of the most promising anode materials for sodium-ion batteries (SIBs) because of its high theoretical capacity upon Na storage (2590 mA h g(-1)), low sodiation potential (approximate to 0.4 V vs. Na/Na+) and natural abundance. Unfortunately, it suffers from huge volume variation during sodiation/desodiation processes, which can cause severe structural destruction and therefore fast performance degradation during cycling. To overcome this issue, tremendous efforts, including nanostructure engineering, composite designing and surface modification, have made to improve the structural stability to optimize the electrochemical performance. Additionally, the fabrication of phosphides is an effective way to achieve P-based anodes with long-cycle life, despite sacrificing a certain amount of capacity. Herein, we first introduce the Na storage mechanism of P-based materials and then summarize the recent advancement in the synthesis and fabrication of phosphorus-based anode materials. The fundamental scientific challenges faced by phosphorus-based electrodes are discussed, followed by a comprehensive review of effective strategies used to enhance the electrochemical properties. We have computed the theoretical sodiation potentials of possible metal phosphides by first-principles calculations, which can offer guidance for future high-performance phosphide exploration. Finally, we discuss the perspectives and challenges to enable the practical applications of P-based materials in SIB. We have attempted to provide a unique insight into this rapidly developing field and shed light on the future trends of the P-based material anodes for SIBs.