Recent advances in transition metal phosphide materials: Synthesis and applications in supercapacitors

Supercapacitors (SCs) are considered promising energy storge systems because of their outstanding power density, fast charge and discharge rate and long-term cycling stability. The exploitation of cheap and efficient electrode materials is the key to improve the performance of supercapacitors. As the battery-type materials, transition metal phosphides (TMPs) possess high theoretical specific capacity, good electrical conductivity and superior structural stability, which have been extensively studied to be electrode materials for supercapacitors. In this review, we summarize the up-to-date progress on TMPs materials from diversified synthetic methods, diverse nanostructures and several prominent TMPs and their composites in application of supercapacitors. In the end, we also propose the remaining challenges toward the rational discovery and synthesis of high-performance TMP electrodes materials for energy storage.