Interfacial Electronic Coupling of NC@WO 3 ‐W 2 C Decorated Ru Clusters as a Reversible Catalyst toward Electrocatalytic Hydrogen Oxidation and Evolution Reactions

Designing a bifunctional catalyst for hydrogen oxidation reaction (HOR) and hydrogen evolution reaction (HER) is significant toward developing sustainable hydrogen‐electric conversion systems. Herein, a cost‐effective bifunctional catalyst, Ru/N‐doped Carbon@WO 3 ‐W 2 C (Ru/NC@WOC), was developed via co‐precipitation and polyol reduction. Ru/NC@WOC showed superior HOR/HER activity in alkaline solution in comparison with commercial Pt/C. HOR electrochemical tests showed that the mass activity at 0.05 V (1.96  m Aμ g R u - 1) and exchange‐current density were 7.5 and 1.2 times that of Pt/C. Additionality, Ru/NC@WOC exhibited up 30‐fold HOR activity in mass activity compared with benchmark Ru/C. Moreover, it also displayed exceptional electrocatalytic HER with overpotentials of 31 mV at 10 mA cm −2 and 119 mV at 100 mA cm −2 , surpassing Pt/C, benchmark Ru/C, and most of the previously reported electrocatalysts. The outstanding catalytic activity of Ru/NC@WOC probably arises from the synergy between Ru and NC@WOC matrix, suitable hydrogen binding energy, and highly conductive substrate. Thus, this work may pave a new avenue to fabricate low‐cost bifunctional HOR/HER catalysts for alkaline fuel cells and water electrolyzer.