In the preparation process of carbon-based transition metal catalysts, the transition metal atoms usually seriously agglomerate, thus reducing the catalytic activity. To slow down the agglomeration of transition metal atoms during high-temperature treatments, herein, organics with coordination functions are proposed to regulate the typical metal-organic framework compound ZIF-67 with rich Co atoms. Electron microscopy structural characterization proves that ZIF-67 modified by coordinated organic compounds, including ascorbic acid (AA), citric acid (CA) and ethylenediaminetetraacetic acid disodium salt (EA), greatly improves the dispersibility of cobalt in the final product. All the adjusted ZIF-67 can derive cobalt-based bifunctional oxygen catalysts with higher activity. Among them, EA-MOF-Co shows the best ORR performance, with a half-wave potential comparable to commercial Pt/C in alkaline solutions and an obviously reduced oxygen evolution overpotential. This suggests that it is an effective method for use of coordination organics to tether metal ions and prevent their further agglomeration during carbonation.

在碳基过渡金属催化剂的制备过程中，过渡金属原子通常会严重团聚，从而降低催化活性。为了减缓高温处理过程中过渡金属原子的团聚，本文提出了具有配位功能的有机物来调节典型的富含Co原子的金属-有机骨架化合物ZIF-67。电镜结构表征证明，ZIF-67经配位有机化合物改性，包括抗坏血酸（AA）、柠檬酸（CA）和乙二胺四乙酸二钠盐（EA），大大提高了钴在最终产品中的分散性。调整后的ZIF-67均可衍生出活性更高的钴基双功能氧催化剂。其中，EA-MOF-Co表现出最好的ORR性能，在碱性溶液中具有与商业 Pt/C 相当的半波电位和显​​着降低的析氧过电位。这表明它是使用配位有机物束缚金属离子并防止它们在碳酸化过程中进一步团聚的有效方法。