Tungsten Carbide Hollow Microspheres with Robust and Stable Electrocatalytic Activity toward Hydrogen Evolution Reaction

Here, we report a stable tungsten carbide hollow microsphere (W2C-HS) electrocatalyst with robust electrocatalytic activity toward hydrogen evolution reaction fabricated from carburization of tungsten oxides at 700 °C with CH4/H2 flow, which demands overpotentials of 153 and 264 mV to deliver 10 and 100 mA cm–2 ascribing to the hollow structures beneficial for interfacial charge transfer as well as releasing of hydrogen molecular. Meanwhile, the W2C-HS electrocatalyst exhibits undetectable degradation after 20 000 potential cycles indicative of extraordinary durability; in contrast, overpotential@100 mA cm–2 is dramatically increased from 128 to 251 mV after only 2000 potential cycles for benchmark platinum electrocatalyst.