Dionigi Fabio, Zhu Jing, Zeng Zhenhua, Merzdorf Thomas, Sarodnik Hannes, Gliech Manuel, Pan Lujin, Li Wei-Xue, Greeley Jeffrey, Strasser Peter
The Electrochemical Energy, Catalysis, and Materials Science Laboratory, Department of Chemistry, Chemical Engineering Division, Technical University Berlin, Strasse des 17. Juni 124, 10623, Berlin, Germany.
School of Chemistry and Materials Science, CAS Excellence Center for Nanoscience, Hefei National Laboratory for Physical Sciences at Microscale, University of Science and Technology of China, Hefei, 230026, Anhui, China.
Angew Chem Int Ed Engl. 2021 Jun 21;60(26):14446-14457. doi: 10.1002/anie.202100631. Epub 2021 May 26.
Layered double hydroxides (LDHs) are among the most active and studied catalysts for the oxygen evolution reaction (OER) in alkaline electrolytes. However, previous studies have generally either focused on a small number of LDHs, applied synthetic routes with limited structural control, or used non-intrinsic activity metrics, thus hampering the construction of consistent structure-activity-relations. Herein, by employing new individually developed synthesis strategies with atomic structural control, we obtained a broad series of crystalline α-M (II)M (III) LDH and β-M (OH) electrocatalysts (M =Ni, Co, and M =Co, Fe, Mn). We further derived their intrinsic activity through electrochemical active surface area normalization, yielding the trend NiFe LDH > CoFe LDH > Fe-free Co-containing catalysts > Fe-Co-free Ni-based catalysts. Our theoretical reactivity analysis revealed that these intrinsic activity trends originate from the dual-metal-site nature of the reaction centers, which lead to composition-dependent synergies and diverse scaling relationships that may be used to design catalysts with improved performance.
层状双氢氧化物（LDHs）是碱性电解质中用于析氧反应（OER）的最具活性且研究最多的催化剂之一。然而，以往的研究通常要么聚焦于少数几种LDHs，采用结构控制有限的合成路线，要么使用非本征活性指标，从而阻碍了一致的结构-活性关系的构建。在此，通过采用新的具有原子结构控制的单独开发的合成策略，我们获得了一系列广泛的结晶α-M（II）M（III）LDH和β-M（OH）电催化剂（M = Ni、Co，以及M = Co、Fe、Mn）。我们通过电化学活性表面积归一化进一步推导了它们的本征活性，得出NiFe LDH > CoFe LDH > 不含铁的含钴催化剂 > 不含铁和钴的镍基催化剂的趋势。我们的理论反应活性分析表明，这些本征活性趋势源于反应中心的双金属位点性质，这导致了与组成相关的协同作用和多样的标度关系，可用于设计性能更优的催化剂。
