Indexed by: Research Article

First Author: Qin,Zhuhuang

Correspondence Author: Li,Qing

Co-author: Huang, Yunhui,Yan, Pengfei,Cao, Rui,Lu, Gang, Shenzhou,Xie, Linfeng,Mao, Jialun,Lai, Jiaoyang,Liu, Xuan,Sathishkumar, Nadaraj,Wu, Qiyan,Li,Jinhui

Journal: Advanced Materials

Affiliation of Author(s): 华中科技大学

Place of Publication: 美国

Document Type: Article

Volume: 36

Issue: 47

Page Number: 2412541

ISSN No.: 1521-4095

Key Words: electrocatalysis; Frank-Kasper C15 phases; hydrogen evolution reaction; intermetallics; proton exchange membrane water electrolyzer

DOI number: 10.1002/adma.202412541

Date of Publication: 2024-09-30

Impact Factor: 27.4

Abstract: Chemical synthesis of unconventional topologically close-packed intermetallic nanocrystals (NCs) remains a considerable challenge due to the limitation of large volume asymmetry between the components. Here, a series of unconventional intermetallic Frank-Kasper C15 phase Ir2M (M = rare earth metals La, Ce, Gd, Tb, Tm) NCs is successfully prepared via a molten-salt assisted reduction method as efficient electrocatalysts for hydrogen evolution reaction (HER). Compared to the disordered counterpart (A1-Ir2Ce), C15-Ir2Ce features higher Ir-Ce coordination number that leads to an electron-rich environment for Ir sites. The C15-Ir2Ce catalyst exhibits excellent and pH-universal HER activity and requires only 9, 16, and 27 mV overpotentials to attain 10 mA cm−2 in acidic, alkaline, and neutral electrolytes, respectively, representing one of the best HER electrocatalysts ever reported. In a proton exchange membrane water electrolyzer, the C15-Ir2Ce cathode achieves an industrial-scale current density of 1 A cm−2 with a remarkably low cell voltage of 1.7 V at 80 °C and can operate stably for 1000 h with a sluggish voltage decay rate of 50 µV h−1. Theoretical investigations reveal that the electron-rich Ir sites intensify the polarization of *H2O intermediate on C15-Ir2Ce, thus lowering the energy barrier of the water dissociation and facilitating the HER kinetics.