Li Xinyi, Wang Ziling, Peng Zijie, Cheng Junfang, Zheng Fenghua, Wang Yuanxing, Tian Yunfeng, Chi Bo, Wei Guanghua, Zhang Junliang
Paris Elite Institute of Technology, Shanghai Jiao Tong University, Shanghai 200240, China.
School of New Energy, Nanjing University of Science and Technology, Jiangyin 214443, China.
ACS Appl Mater Interfaces. 2024 Oct 23;16(42):57099-57111. doi: 10.1021/acsami.4c12171. Epub 2024 Oct 9.
Designing catalysts with desirable oxygen evolution reaction (OER) performance under pH-universal conditions is of great significance to promote the development of hydrogen production. Herein, we successfully synthesized a crystalline-amorphous IrO supported on perovskite oxide nanotubes to obtain IrO@LaCaFeNiO with superior OER performance in whole pH media. The overpotential of the IrO@LaCaFeNiO catalyst in media of pH 14, 7.2, and 1 has been demonstrated to be 120, 400, and 143 mV, respectively, with no significant element dissolution as well as double-layer capacitance decay after the durability test. Through comparative experiments with IrO@CNT and the physical mixture of IrO and LaCaFeNiO, it is found that the strong metal-support interaction (SMSI) in IrO@LaCaFeNiO makes IrO exist in an amorphous state rich in Ir, which is closely associated with the surface-active species Ir-OH. Through the regulation of Ir by a perovskite oxide support at the heterointerface, the reaction breaks through the limitation of the adsorbate evolution mechanism (AEM) and converts to a lattice-oxygen-mediated mechanism (LOM), which was fully demonstrated by the addition of the probe tetramethylammonium cation (TMA), a LOM reaction intermediate, to the electrolyte. This work fills the research gap of perovskite oxide supported Ir-based catalysts with heterogeneous structures, providing an excellent strategy for the structural design of efficient pH-universal OER catalysts for hydrogen production systems.
设计在pH通用条件下具有理想析氧反应（OER）性能的催化剂对于促进制氢发展具有重要意义。在此，我们成功合成了负载在钙钛矿氧化物纳米管上的晶态-非晶态IrO，以获得在全pH介质中具有优异OER性能的IrO@LaCaFeNiO。IrO@LaCaFeNiO催化剂在pH值为14、7.2和1的介质中的过电位分别为120、400和143 mV，在耐久性测试后没有明显的元素溶解以及双层电容衰减。通过与IrO@CNT以及IrO和LaCaFeNiO的物理混合物的对比实验发现，IrO@LaCaFeNiO中的强金属-载体相互作用（SMSI）使Ir以富含Ir的非晶态存在，这与表面活性物种Ir-OH密切相关。通过在异质界面处用钙钛矿氧化物载体对Ir进行调控，该反应突破了吸附物演化机制（AEM）的限制，转变为晶格氧介导机制（LOM），这通过向电解质中添加探针四甲基铵阳离子（TMA）（一种LOM反应中间体）得到了充分证明。这项工作填补了具有异质结构的钙钛矿氧化物负载Ir基催化剂的研究空白，为制氢系统高效pH通用OER催化剂的结构设计提供了优异策略。
