Polyoxometalates hydrogels derived porous conductive Pt@Mo ₂ C carbon aerogels as self‐supporting electrocatalysts for enhancing alkaline hydrogen evolution reaction

Abstract The kinetics of alkaline hydrogen evolution reaction (HER) of platinum (Pt) is markedly slower owing to the poor proton supply rate and sluggish water dissociation. Herein, we report an efficient strategy based on polyoxometalates (POMs) hydrogels to prepare the self‐supporting porous conductive carbon aerogels embedded with Pt‐doped molybdenum carbide (Pt@Mo 2 C) active sites for promoting the alkaline HER performance. It is found that as‐prepared self‐supporting Pt@Mo 2 C carbon aerogels possesses continuous porous conductive networks, which improves the electron and mass transfer. Moreover, the heterostructure of Pt and Mo 2 C can significantly promote the water dissociation with the assistant of Mo‐OH and Pt–H bonding, thereby improving alkaline HER activities. The optimized Pt@Mo 2 C/Carbon fiber paper (Pt@Mo 2 C/CFP) electrocatalyst has Pt content as low as 0.03 mg cm −2 , which can achieve overpotential of 17 mV at 10 mA cm −2 , surpassing the commercial Pt/C. Moreover, it exhibits an excellent sustained stability for over 100 h at 500 mA cm ‐2 in a practical alkaline water electrolyzer. The work offers new opportunities to design and synthesize superior performance electrocatalysts for the alkaline HER.