Tuning the Electronic Structures of TMNs‐Modified Ni‐Based Catalysts to Enhance the Performance for MOR in Alkaline Media

Abstract

AbstractTransition metal nitrides are considered as the promising materials in the energy conversion processes due to the similar electronic structures to Pt. In this work, a series of Ni/TMN−C (TM=V, Mo, Nb, Ta) catalysts were synthesized and investigated the catalytic performance for methanol oxidation reaction in alkaline media. The electrochemical measurements indicated that the TNNs‐modified Ni/C catalysts exhibited higher activity, kinetics, charge transfer and stability for alkaline MOR compared with Ni/C. It was found that the incorporation of TMNs improved the activity and stability for MOR in various degree. Specially, Ni/VN−C showed the highest catalytic activity, nearly three times higher than that of Ni/C due to the highest coverage of the surface component NiOOH, consistent with the Tafel and EIS results that it exhibited the fastest charge transfer kinetics and reaction rate. XPS characterization indicated that the obvious electron interaction occurred between the TMNs and Ni species and Ni would transfer electrons to the transition metal nitrides, resulting in the electron‐rich states of TMNs. Interestingly, combining the d‐band center and activity of the corresponding catalysts, it could be found that a volcano plot existed between them, suggesting that the introduction of appropriate nitrides would change the electronic structure of Ni and enhance the catalytic performance for MOR in alkaline media.