Supported nanostructures of oxygen evolution catalysts with three-dimensional (3-D) architectures are promising for significantly boosting the oxygen evolution reaction (OER) efficiency, but are difficult to fabricate. We report the synthesis of 3-D interconnected pristine graphene supported NiO nanosheets via in situ self-assembly. Its overpotential at 10 mA cm⁻² is 320 mV and Tafel slope is 52.4 mV dec⁻¹, both of which are lower than most reported values of NiO-based catalysts and even Ir and Ru-based ones. It exhibits only a slight loss of the current density after 20 h of chronoamperometric measurement at an overpotential of 320 mV (from 10.09 to 9.62 mA cm⁻²) and a small increase after 1000 CV cycles (from 41.47 to 46.01 mA cm⁻² at 1.58 V). The synthesis of NiO nanosheets on graphene offers key insights into the self-assembly mechanism. The reported in situ self-assembly of metal oxide nanostructures with 3-D architecture on graphene is a low-cost, facile and mild strategy for making high-performance OER catalyst demonstrating the advantages of 3-D interconnected nanostructures supported on graphene.

具有三维（3-D）结构的氧析出催化剂的负载纳米结构有望显着提高氧析出反应（OER）的效率，但难以制造。我们通过原位自组装报告了3-D互连的原始石墨烯支持的NiO纳米片的合成。其在10 mA cm ^-2处的过电势为320 mV，Tafel斜率为52.4 mV dec ^-1，均低于大多数报道的NiO基催化剂甚至Ir和Ru基催化剂的值。在计时电位测量20小时后，在320 mV（从10.09到9.62 mA cm ^-2）的超电势下，电流密度仅显示出轻微的损失，而在1000 CV循环后（从41.47到46.01 mA cm）显示出很小的电流密度损失。在1.58 V时为^-2）。石墨烯上NiO纳米片的合成为自组装机理提供了重要见解。已报道的在石墨烯上具有3-D结构的金属氧化物纳米结构的原位自组装是一种低成本，简便且温和的制备高性能OER催化剂的策略，证明了在石墨烯上负载的3-D互连纳米结构的优势。