Boosting neutral hydrogen evolution reaction on iridium by support effect of W18O49

• Published in: Applied catalysis. A, General Vol. 623; p. 118293
• Main Authors: Peng, Chunlei, Zhao, Wanpeng, Kuang, Zhaoyu, Miller, Jeffrey T., Chen, Hangrong
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 05-08-2021; Elsevier Science SA
• Subjects: Electron transfer; Hydrogen evolution reaction; Hydrogen evolution reactions; Iridium; Iridium nanoparticles; Kinetics; Nanowires; Protons; Support effect; Tungsten oxide; Tungsten oxides; Water chemistry; Water splitting; Tungsten oxide; Hydrogen evolution reaction; Iridium nanoparticles; Water-splitting; Support effect
• ISSN: 0926-860X; 1873-3875
• DOI: 10.1016/j.apcata.2021.118293

Catalyst-support effect is an attractive topic in catalysis area. Tungsten oxide support was found to enhance the performance of HER under neutral medium by different ways. Acceleration effect on the dissociation water molecules could favor the cleavage step of H2O to facilitate the subsequent process. Moreover, the better electron transfer capability contributes to the kinetics of HER. Meanwhile, the “proton container” effect could change the reaction pathway in the beginning of reaction.
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•The constructed Ir/W18O49 achieves enhanced neutral HER performance by the support effect.•W18O49 carrier could facilitate Volmer step during neutral HER.•The prepared W18O49 has faster electron transfer capability contributing to faster kinetics.•The prepared W18O49 shows interesting “proton container” property.
Neutral electrochemical water splitting is an environmentally benign method to obtain hydrogen directly from water, which is highly desired but still in challenge since hydrogen evolution reaction (HER) under neutral condition suffers from sluggish kinetics. In this work, a novel 10 %wt Ir/W18O49 nanowire catalyst was developed to enhance the performance of HER under neutral medium by using tungsten oxide as support. It is found that tungsten oxide support endows better electron transfer capability contributing to faster kinetics, and more importantly tungsten oxide could effectively accelerate dissociation of the water molecule step promoting Volmer step to favor the subsequent reaction on Ir active sites. Consequently, enhanced activity with overpotential of 83 mV at 10 mA cm−2 was achieved for neutral HER. Meanwhile, an interesting “proton container” property was found in the tungsten oxide support, which could release protons at the beginning of reaction to enable HER via acidic pathway achieving improved performance.