Crystalline/Amorphous‐Ru/VOx Phase Engineering Expedites The Alkaline Hydrogen Evolution Kinetics

• Published in: Advanced functional materials Vol. 34; no. 19
• Main Authors: Tao, Zhenhua, Zhao, Hongyu, Lv, Ning, Luo, Xu, Yu, Jun, Tan, Xin, Mu, Shichun
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc 10.05.2024
• Subjects: Alkalinity; Catalysts; Charge transport; crystalline‐amorphous heterointerface; electrocatalysis; electronic metal‐support interaction; Heat treatment; High temperature; hydrogen evolution reaction; Hydrogen evolution reactions; Industrial applications; phase engineering; Reaction intermediates; Reaction kinetics; Ruthenium; Solid phases
• ISSN: 1616-301X; 1616-3028
• DOI: 10.1002/adfm.202312987

Active and durable catalysts for hydrogen evolution reaction (HER) are of great significance for developing renewable hydrogen energy. Herein, crystalline/amorphous‐Ru/VOx (c/a‐Ru/VOx) heterogeneous catalysts are conceived, in which the amorphous VOx exposes more active sites and enhances charge transport compared with the counterpart with a crystal phase structure, strengthening the electronic interaction between metal‐support. As expected, c/a‐Ru/VOx‐500 with heat treatment at 500 °C exhibits excellent HER performance under alkaline conditions, with an overpotential of only 33 mV at 10 mA cm−2 and small Tafel slope (27 mV dec−1), superior to commercial platinum/carbon (Pt/C) catalysts. Particularly, its mass activity (0.335 A mgRu−1) is 1.5 times greater than that of Pt/C (0.224 A mgPt−1) at an overpotential of 50 mV. Also, it shows good industrial application prospects through tests under high temperature, high alkalinity, and large current conditions. Theoretical calculations unveil that there exists a charge redistribution at c/a‐Ru/VOx heterointerfaces, which makes the surface of Ru takes on an electron‐deficient state, resulting in optimization of adsorption and desorption for different reaction intermediates. This optimized behavior effectively reduces the thermodynamic energy barrier, allowing the catalyst with greatly enhanced HER performance. The exploration provides a promising strategy for designing efficient and durable catalysts for HER. A crystal/amorphous heterojunction catalyst (c/a‐Ru/VOx) with strong metal substrate interaction is proposed, in which the amorphous VOx substrate reduces the d‐band center of the surface ruthenium, optimizes the hydrogen adsorption energy of Ru sites, thereby allowing the catalyst with Pt‐like hydrogen evolution reaction kinetics.