Li Gengnan, Priyadarsini Adyasa, Xie Zhenhua, Kang Sinwoo, Liu Yuzi, Chen Xiaobo, Kattel Shyam, Chen Jingguang G
Center for Nanoscale Materials, Argonne National Laboratory, Lemont, Illinois 60439, United States.
Department of Physics, Florida A&M University, Tallahassee, Florida 32307, United States.
J Am Chem Soc. 2025 Feb 26;147(8):7008-7016. doi: 10.1021/jacs.4c17915. Epub 2025 Feb 13.
The development of electrocatalysts with reduced iridium (Ir) loading for the oxygen evolution reaction (OER) is essential to produce low-cost green hydrogen from water electrolysis under acidic conditions. Herein, an atomically thin layer of iridium oxide (IrO) has been uniformly dispersed onto cobalt oxide (CoO) nanocrystals to improve the efficient use of Ir for acidic OER. In situ characterization and theoretical calculations reveal that compared to the conventional IrO cluster, the atomically thin layer of IrO shows stronger interaction with the CoO and consequently higher OER activity due to the Ir-O-Co bond formation at the interface. Equally important, the facile synthetic method and the promising activity in the proton exchange membrane water electrolyzer, reaching 1 A cm at 1.7 V with remarkable durability, enable potential scale-up applications. These findings provide a mechanistic understanding for designing active, stable and lower-cost electrocatalysts with well-defined structures for acidic OER.
开发用于析氧反应（OER）的低铱（Ir）负载量的电催化剂对于在酸性条件下通过水电解生产低成本绿色氢气至关重要。在此，氧化铱（IrO）原子薄层已均匀分散在氧化钴（CoO）纳米晶体上，以提高Ir在酸性OER中的有效利用率。原位表征和理论计算表明，与传统的IrO簇相比，IrO原子薄层与CoO表现出更强的相互作用，因此由于在界面处形成Ir-O-Co键而具有更高的OER活性。同样重要的是，这种简便的合成方法以及在质子交换膜水电解槽中具有的良好活性（在1.7 V下达到1 A cm且具有出色的耐久性），使其具有潜在的扩大应用规模的可能性。这些发现为设计用于酸性OER的具有明确结构的活性、稳定且低成本的电催化剂提供了机理理解。
