Pt Atom-Substituted MoC Single-Atom Catalyst for Enhancing H<sub>2</sub> Production
Nanfang Tang, Dongyuan Liu, Shuai Chen, Zhenyu Wang, Yuxia Ma, Qi Li, Yunshuai Li, Guoliang Xu, Chuntian Wu, Liqun Kang, Wenhao Luo, Botao Qiao, Houyu Zhu, Yu Cong
Abstract
Single-atom catalysts with a maximum atom utilization efficiency have shown great potential for application in energy conversion and storage fields. Herein, a highly stable single-atom Pt catalyst (Pt 1 /α-MoC) on α-MoC nanoribbons with Pt loading up to 2% is fabricated using an atom substitution strategy for the water–gas shift (WGS) reaction, which exhibits a very high H 2 production rate of 1094 μmol CO /g cat s at 200 °C, indicating one of the highest activity levels compared with the reported state-of-the-art WGS catalysts. Complementary advanced characterizations, including aberration-corrected scanning transmission electron microscopy (STEM), synchrotron X-ray absorption spectroscopy (XAS), and density functional theory (DFT) calculations, demonstrate that single Pt atoms are uniformly dispersed on the outermost surface of α-MoC and strongly confined within the crystalline lattice of molybdenum carbides. In situ spectroscopic studies and DFT calculations reveal that the Pt-MoC interface serves as a primary active site of the water gas shift (WGS) reaction, boosting H 2 O molecule activation, to form the key OH* intermediates. Our findings offer an efficient method for the rational design of high-activity single-atom catalysts and lay a good foundation for their industrial application.