Single-Atomic Ir and Mo Co-Confined in a Co Layered Hydroxide Nanobox Mutually Boost Oxygen Evolution
Rouna Jia, Meihan Xia, Lei Tang, Liang Yu, Yan Yang, Yunlong Zhang, Xin Bo, Shizheng Zhou, Yunchuan Tu, Dehui Deng
Abstract
The sluggish four-electron-transfer kinetics of the oxygen evolution reaction (OER) is a great challenge for the development of efficient and cost-effective OER electrocatalysts. Herein, we report single-atomic Ir and Mo co-confined in the lattice of a Co layered hydroxide (Co-LH) nanobox as an efficient OER electrocatalyst via a sacrificial template method. With the hollow structure and synergetic electronic interactions among Ir, Mo, and Co-LH, the catalyst delivers an ultralow overpotential of 220 mV at 10 mA cm–2 and high durability of over 800 h at 50 mA cm–2 in 1 M KOH, which significantly outperform the commercial Ir black catalyst. Density functional theory calculations indicate that adjacent Mo and Ir enhance the OER activities on the Ir sites at defects (defect-Ir) and Mo sites in the plane (in-plane-Mo), respectively. This study provides not only a highly efficient OER catalyst but also a strategy for confining dual-active centers with mutually improved catalytic activities.