Role of Oxidized Mo Species on the Active Surface of Ni-Mo Electrocatalysts for Hydrogen Evolution under Alkaline Conditions

被引：104

作者：

Bau, Jeremy A. ^{[1
]}

Kozlov, Sergey M. ^{[1
,2
]}

Miguel Azofra, Luis ^{[1
,3
]}

Ould-Chikh, Samy ^{[1
]}

Emwas, Abdul-Hamid ^{[4
]}

Idriss, Hicham ^{[5
]}

Cavallo, Luigi ^{[1
]}

Takanabe, Kazuhiro ^{[1
,6
]}

机构：

[1] King Abdullah Univ Sci & Technol KAUST, KAUST Catalysis Ctr KCC, Thuwal 239556900, Saudi Arabia

[2] Natl Univ Singapore, Dept Chem & Biomol Engn, Singapore 117585, Singapore

[3] Univ Las Palmas de Gran Canaria ULPGC, Inst Estudios Ambientales & Recursos Nat I UNAT, Las Palmas Gran Canaria 35017, Spain

[4] King Abdullah Univ Sci & Technol KAUST, KAUST Imaging & Characterizat Core Lab, Thuwal 239556900, Saudi Arabia

[5] Saudi Arabian Basic Ind Corp SABIC, Ctr Res & Dev, Thuwal 239556900, Saudi Arabia

[6] Univ Tokyo, Sch Engn, Dept Chem Syst Engn, Tokyo 1138656, Japan

来源：

ACS CATALYSIS | 2020年 / 10卷 / 21期

关键词：

nickel; molybdenum; hydrogen evolution; alkaline; EPR;

D O I：

10.1021/acscatal.0c02743

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

A Ni-Mo composite functions as a promising non-noble metal electrocatalyst for the hydrogen evolution reaction (HER) in alkaline water. Despite its industrial relevance, the kinetic origin of the high catalytic activity remains under debate. The present report discusses a reaction mechanism of HER on Ni-Mo catalysts by combining experimental and theoretical studies. In contrast to a Ni catalyst, a Ni-Mo catalyst is insensitive to CO gas introduced during HER. In situ spectroscopic measurements including Raman spectroscopy and electron paramagnetic resonance (EPR) show that Mo3+ prevails during HER catalysis. Density functional theory (DFT) simulations corroborate the thermodynamic stability and HER activity of Mo3+-containing centers on Ni(111) at HER potentials. Notably, Ni is demonstrated to play no direct role as a catalytic site but to effectively disperse and activate the oxidized catalytic Mo species. The results illustrate how to improve the electrocatalytic activity for alkaline HER.

引用

页码：12858 / 12866

页数：9

共 52 条

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