Highly efficient and stable earth-abundant metal electrocatalysts are of great significance for improving water splitting systems and rechargeable metal–air batteries, in which the oxygen evolution reaction (OER) plays a central part. Among other strategies, anchoring metal–organic frameworks (MOFs) onto conductive materials has proven fruitful towards enhancing their OER performance. Here we explore two strategies for covalent functionalization of graphene flakes as templates for in situ growth of a bimetallic MOF (NiCo-H₂bpydc) that is formed using 2,2′-bipyridine-5,5′-dicarboxylic acid as the organic linker, and Ni²⁺/ Co²⁺ (1:1) as the metal nodes. The graphene template modified with low density functional groups preserves the original octahedral shape of 3D NiCo-H₂bpydc, while functionalization with high density functional groups transforms the MOF octahedra into nanoflowers with ‘desert rose’ morphology, leading to increased accessible active sites, electric conductivity and enlarged active surface area, thus boosting the OER performance with a small overpotential (241 mV) at 10 mA cm⁻² in alkaline solution. This synthetic strategy therefore presents an efficient pathway towards controlling morphology and properties of graphene supported electrocatalytic materials with excellent OER performance.

高效稳定的地球丰富的金属电催化剂对于改进水分解系统和可充电金属-空气电池具有重要意义，其中析氧反应（OER）起着核心作用。在其他策略中，将金属有机框架 (MOF) 锚定到导电材料上已被证明对提高其 OER 性能卓有成效。在这里，我们探索了石墨烯薄片共价功能化的两种策略，作为双金属 MOF (NiCo-H _{2 bpydc)}原位生长的模板，该双金属 MOF使用 2,2'-联吡啶-5,5'-二羧酸作为有机连接剂形成, 和 Ni ²⁺ / Co ²⁺(1:1) 作为金属节点。用低密度官能团修饰的石墨烯模板保留了 3D NiCo-H ₂ bpydc 的原始八面体形状，而用高密度官能团官能化将 MOF 八面体转变为具有“沙漠玫瑰”形态的纳米花，从而增加了可及的活性位点，电电导率和扩大的活性表面积，从而提高 OER 性能，在碱性溶液中 10 mA cm ^{-2时具有较小的过电势 (241 mV)。}因此，这种合成策略为控制具有优异 OER 性能的石墨烯负载电催化材料的形态和性能提供了一条有效途径。