General Construction of Molybdenum‐Based Nanowire Arrays for pH‐Universal Hydrogen Evolution Electrocatalysis

Abstract Robustly integrated electrodes constructed by well‐organized building blocks of active materials are appealing in versatile electrochemical systems. Herein, orderly oriented nanowire arrays (NWAs) of multiple molybdenum‐based compounds (MoX n , MoX n = MoP, MoS 2 , Mo 2 C, MoN, and MoO 2 ) on carbon fiber paper (CFP) are generally fabricated by topotactic transformations from molybdenum‐containing precursor NWAs. Extensive structural characterizations reveal that these MoX n nanowires are composed of either closely interconnected nanoparticles or edge‐rich nanosheets. When being used as self‐supported electrodes, these MoX n NWAs/CFP exhibit excellent catalytic activities and stabilities toward hydrogen evolution reaction (HER) in pH‐universal electrolytes. Especially, the best‐performed MoP NWAs/CFP shows comparable or even superior HER performance over platinum benchmark, which holds great promises in HER‐related energy technologies. This work presents a simple yet effective approach toward general synthesis of self‐supported Mo‐based NWAs on CFP, which also possesses huge application prospects in other fields, such as supercapacitors, batteries, and sensors.