High-Entropy Alloy Nanosheets for Fine-Tuning Hydrogen Evolution

• Published in: ACS catalysis 2022-10, Vol.12 (19), p.11955-11959
• Main Authors: Fu, Xianbiao, Zhang, Jiahao, Zhan, Shaoqi, Xia, Fanjie, Wang, Chengjie, Ma, Dongsheng, Yue, Qin, Wu, Jinsong, Kang, Yijin
• Format: Article
• Language: English
• Subjects: electrocatalysis; high-entropy alloy; hydrogen binding energy; hydrogen evolution reaction; two-dimensional materials
• ISSN: 2155-5435; 2155-5435
• DOI: 10.1021/acscatal.2c02778

The electrolysis of water is promising for hydrogen production. The development of high-performance and low-cost hydrogen evolution reaction (HER) electrocatalysts is particularly important for the wide application of water electrolyzers. Tuning the hydrogen binding energy (HBE) of materials is an effective way to optimize the HER electrocatalysts, particularly for applications in an acidic environment. Here, we report the discovery of a Pt-free combination, PdMoGaInNi, which has the HBE optimum, via computer-facilitated screening. As the exploratory example of the two-dimensional high-entropy alloy (HEA) for HER, the PdMoGaInNi HEA nanosheets were synthesized to realize the predicted Pt-free combination with optimal HBE. The PdMoGaInNi HEA nanosheets exhibit a high HER activity with low overpotentials of 13 mV at 10 mA cm–2, outperforming commercial Pd/C and Pt/C catalysts. Given the high entropy, lattice distortion, and sluggish diffusion effects of HEA, the PdMoGaInNi shows great long-term durability for at least 200 h in a proton exchange membrane water electrolyzer.