Lu Min, Zheng Yao, Hu Yang, Huang Bolong, Ji Deguang, Sun Mingzi, Li Jianyi, Peng Yong, Si Rui, Xi Pinxian, Yan Chun-Hua
State Key Laboratory of Applied Organic Chemistry, Frontiers Science Center for Rare Isotopes, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, China.
School of Chemical Engineering and Advanced Materials, The University of Adelaide, Adelaide, South Australia 5005, Australia.
Sci Adv. 2022 Jul 29;8(30):eabq3563. doi: 10.1126/sciadv.abq3563.
The regulation of mechanism on the electrocatalysis process with multiple reaction pathways is more efficient and essential than conventional material engineering for the enhancement of catalyst performance. Here, by using oxygen evolution reaction (OER) as a model, which has an adsorbate evolution mechanism (AEM) and a lattice oxygen oxidation mechanism (LOM), we demonstrate a general strategy for steering the two mechanisms on various LaSrCoO. By delicately controlling the oxygen defect contents, the dominant OER mechanism on LaSrCoO can be arbitrarily transformed between AEM-LOM-AEM accompanied by a volcano-type activity variation trend. Experimental and computational evidence explicitly reveal that the phenomenon is due to the fact that the increased oxygen defects alter the lattice oxygen activity with a volcano-type trend and preserve the Co state for preferably OER. Therefore, we achieve the co-optimization between the activity and stability of catalysts by altering the mechanism rather than a specific design of catalysts.
对于提高催化剂性能而言，调控具有多种反应途径的电催化过程的机制比传统材料工程更高效且至关重要。在此，我们以析氧反应（OER）为模型，该反应具有吸附质演化机制（AEM）和晶格氧氧化机制（LOM），展示了一种在各种LaSrCoO上引导这两种机制的通用策略。通过精确控制氧缺陷含量，LaSrCoO上主导的OER机制可以在AEM - LOM - AEM之间任意转变，同时伴随着火山型活性变化趋势。实验和计算证据明确表明，该现象是由于增加的氧缺陷以火山型趋势改变了晶格氧活性，并保留了有利于OER的Co状态。因此，我们通过改变机制而非对催化剂进行特定设计，实现了催化剂活性和稳定性之间的协同优化。
