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

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 (MoXn, MoXn = MoP, MoS2, Mo2C, MoN, and MoO2) on carbon fiber paper (CFP) are generally fabricated by topotactic transformations from molybdenum-containing precursor NWAs. Extensive structural characterizations reveal that these MoXn nanowires are composed of either closely interconnected nanoparticles or edge-rich nanosheets. When being used as self-supported electrodes, these MoXn 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.