Hierarchical WMoC nano array with optimal crystal facet as a non-noble metal cathode for proton exchange membrane water electrolyser

Highly efficient non-noble metal hydrogen evolution reaction (HER) catalysts are of particular importance for cost-effective proton exchange membrane water electrolyser (PEMWE). Here, hierarchical WMoC nano arrays (NAs) with superhydrophilic surface and optimal crystal facet is synthesized. Mo plays a crucial role in preferred growth of active crystal facet and the formation of NA. Thanks to the optimal crystal facet and unique structure, WMoC NA exhibits an enhanced HER activity and stability under high current density. PEMWE single cell based on WMoC cathode shows an outstanding performance, which obtains a current density of 1 A cm−2 at voltage of 1.888 V with N117 at 80 °C, making it one of the best PEMWEs using non-noble metal cathode. The single cell also shows a stable operation under 1A cm−2 at 80 °C over 700 h, demonstrating WMoC cathode's great potential for application use.