中国科学院长春应化所董绍俊团队报道高效氧还原用钯钼碳化物的界面电子工程策略。 相关研究成果于2021年4月29日发表于国际顶尖学术期刊《美国化学会杂志》。

贵金属与过渡金属碳化物之间的界面电子工程是提高电催化氧还原反应（ORR）本征活性的有效手段。然而，这种短程效应和巨大的结构差异使得获得具有原子薄贵金属层的电催化剂成为一个重大挑战。

该文中，研究人员展示了通过精确控制金属-有机骨架约束和共价相互作用来制备Mo2C耦合Pd原子层（AL-Pd/Mo2C）异质结构电催化剂的组合策略。原子表征和密度泛函理论计算均表明，强电子效应对Pd原子层的电子结构和d带中心有强烈的调节作用，从而优化了反应动力学。值得注意的是，AL-Pd/Mo2C表现出最高的ORR电化学活性和稳定性，在0.9V下的质量活性为2.055AmgPd-1，分别是Pt/C、Pd/C和Pd纳米粒子的22.1、36.1和80.3倍。

该研究为贵金属原子催化剂的制备提供了一种新的方法，为界面电子调控提供了新的思路。

附：英文原文

Title: Interfacial Electron Engineering of Palladium and Molybdenum Carbide for Highly Efficient Oxygen Reduction

Author: Liang Huang, Xiliang Zheng, Ge Gao, He Zhang, Kai Rong, Jinxing Chen, Yongqin Liu, Xinyang Zhu, Weiwei Wu, Ying Wang, Jin Wang, Shaojun Dong

Issue&Volume: April 29, 2021

Abstract: Interfacial electron engineering between noble metal and transition metal carbide is identified as a powerful strategy to improve the intrinsic activity of electrocatalytic oxygen reduction reaction (ORR). However, this short-range effect and the huge structural differences make it a significant challenge to obtain the desired electrocatalyst with atomically thin noble metal layers. Here, we demonstrated the combinatorial strategies to fabricate the heterostructure electrocatalyst of Mo2C-coupled Pd atomic layers (AL-Pd/Mo2C) by precise control of metal–organic framework confinement and covalent interaction. Both atomic characterizations and density functional theory calculations uncovered that the strong electron effect imposed on Pd atomic layers has intensively regulated the electronic structures and d-band center and then optimized the reaction kinetics. Remarkably, AL-Pd/Mo2C showed the highest ORR electrochemical activity and stability, which delivered a mass activity of 2.055 A mgPd–1 at 0.9 V, which is 22.1, 36.1, and 80.3 times higher than Pt/C, Pd/C, and Pd nanoparticles, respectively. The present work has developed a novel approach for atomically noble metal catalysts and provides new insights into interfacial electron regulation.

DOI: 10.1021/jacs.1c00656

Source: https://pubs.acs.org/doi/10.1021/jacs.1c00656