Enriched Oxygen Coverage Localized within Ir Atomic Grids for Enhanced Oxygen Evolution Electrocatalysis
Year: 2024
Type: article
Abstract: Inefficient active site utilization of oxygen evolution reaction (OER) catalysts have limited the energy efficiency of proton exchange membrane (PEM) water electrolysis. Here, an atomic grid structure is demonstrated composed of high‐density Ir sites (≈10 atoms per nm 2 ) on reactive MnO 2–x support which mediates oxygen coverage‐enhanced OER process. Experimental characterizations verify the low‐valent Mn species with decreased oxygen coordination in MnO 2–x exert a pivotal impact in the enriched oxygen coverage on the surface during OER process, and the distributed Ir atomic grids, where highly electrophilic Ir─O (II‐δ)− bonds proceed rapidly, render intense nucleophilic attack of oxygen radicals. Thereby, this metal‐support cooperation achieves ultra‐low overpotentials of 166 mV at 10 mA cm −2 and 283 mV at 500 mA cm −2 , together with a striking mass activity which is 380 times higher than commercial IrO 2 at 1.53 V. Moreover, its high OER performance also markedly surpasses the commercial Ir black catalyst in PEM electrolyzers with long‐term stability.
Source: Advanced Materials
Language: English
Field: Energy
Domain: Physical Sciences
Open Access status: bronze
Funders: Salt Science Research Foundation, National Natural Science Foundation of China, Science and Technology Commission of Shanghai Municipality, Shanghai Rising-Star Program, National Key Research and Development Program of China, Fundamental Research Funds for the Central Universities, Beijing Synchrotron Radiation Facility
OpenAlex ID: W4401820491