Transition-Metal Phosphides: Activity Origin, Energy-Related Electrocatalysis Applications, and Synthetic Strategies

Developing highly efficient and stable electrocatalysts plays an important role in energy-related electrocatalysis fields. Transition-metal phosphides (TMPs) possess a series of advantages, such as high conductivity, earth-abundance reserves, and good physicochemical properties, therefore arousing wide attention. In this review, the electrochemical activity origin of TMPs, allowing the rational design and construction of phosphides toward various energy-relevant reactions is first discussed. Subsequently, their unique energy-related electrocatalysis nature toward hydrogen evolution reaction (HER), oxygen evolution reaction (OER), oxygen reduction reaction (ORR), hydrogen oxidation reaction (HOR), carbon dioxide reduction reaction (CO2RR), nitrogen reduction reaction (NRR), urea oxidation reaction (UOR), methanol oxidation reaction (MOR), and others is highlighted. Then, the TMPs' synthetic strategies are analyzed and summarized systematically. Finally, the existing key issues, countermeasures, and the future challenges of TMPs toward efficient energy-related electrocatalysis are briefly discussed.