Abstract Oxygen electrocatalysis, exemplified by the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), is central to energy storage and conversion technologies such as fuel cells, metal-air batteries, and water electrolysis. However, highly effective and inexpensive earth-abundant materials are sought after to replace the noble metal-based electrocatalysts currently in use. Recently, metal-organic frameworks (MOFs) and carbon-based MOF derivatives have attracted considerable attention as efficient catalysts due to their exceedingly tunable morphologies, structures, compositions, and functionalization. Here, we report two-dimensional (2D) MOF/MOF derivative coupled arrays on nickel foam as binder-free bifunctional ORR/OER catalysts with enhanced electrocatalytic activity and stability. Their remarkable electrochemical properties are primarily attributed to fully exposed active sites and facilitated charge-transfer kinetics. The coupled and hierarchical nanosheet arrays produced via our growth-pyrolysis-regrowth strategy offer promise in the development of highly active electrodes for energy-related electrochemical devices.

中文翻译：

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泡沫镍上的二维 MOF/MOF 衍生物阵列作为高效的双功能耦合氧电极

摘要 以氧还原反应 (ORR) 和析氧反应 (OER) 为代表的氧电催化是燃料电池、金属空气电池和水电解等能量存储和转换技术的核心。然而，人们正在寻求高效且廉价的地球资源丰富的材料来替代目前使用的贵金属基电催化剂。最近，金属有机骨架 (MOF) 和碳基 MOF 衍生物由于其极其可调的形态、结构、组成和功能化，作为高效催化剂引起了相当多的关注。在这里，我们报告了泡沫镍上的二维 (2D) MOF/MOF 衍生物耦合阵列作为无粘合剂的双功能 ORR/OER 催化剂，具有增强的电催化活性和稳定性。它们卓越的电化学性能主要归因于完全暴露的活性位点和促进的电荷转移动力学。通过我们的生长-热解-再生长策略产生的耦合和分层纳米片阵列为开发用于能源相关电化学设备的高活性电极提供了希望。