Hollow-structured and Polyhedron-Shaped High Entropy Oxide Towards Highly Active And Robust Oxygen Evolution Reaction in A Full Ph Range.

High entropy metal oxides (HEO) are superior to many reactions involving multi-step elementary reactions. However, controlled synthesis of hollow-structured HEO catalysts, which offers large surface area and fast mass transfer kinetics, remains challenging and unexplored due to the complicated metal precursors. Herein, a metal organic framework-templated synthesis of hollow-structured and polyhedron-shaped HEO catalysts assembled with ultra-small nanoparticles, with up to ten metal elements, can be achieved, by taking advantage of the ion-exchange method. ZnFeNiCuCoRu-O HEO catalyst displays excellent activity and ultra-stability for oxygen evolution reaction (OER) in full pH range, with an overpotential of 170 mV at a current density of 10 mA cm -2 , a Tafel slope of 56 mV dec -1 , and a decay of activity by 7% in 30 h in alkaline medium, as well as a 12% and 8% decay in acidic and neutral medium, respectively. DFT calculation indicates that the energy barrier of the potential determining step on Ru-Fe bridge site is significantly lower than any other Ru-related bridge sites for the unique hollow structured HEO structures. This work highlights the importance of ion-exchange method in preparing highly stable and active hollow-structured HEOs catalysts towards highly efficient energy conversion and storage devices. This article is protected by copyright. All rights reserved.