Novel CoFe-LDH (layered double hydroxide) nanosheet arrays in situ grown on rGO (reduced graphene oxide) uniformly modified Ni foam were synthesized by a citric acid-assisted aqueous phase coprecipitation strategy. Systematic characterizations indicates that the series of Co_xFe₁-LDH/rGO/NF (x = 4, 3, 2) all show Co_xFe₁-LDH nanosheets (150–180 × 15 nm) grown vertically on the surface of rGO/NF. Especially, the Co₃Fe₁-LDH/rGO/NF exhibits the best performance with overpotentials of 250 and 110 mV at 10 mA cm⁻² in 1 M KOH for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER), respectively. When it is used as cathode and anode simultaneously for overall water splitting, they require 1.65 and 1.84 V at 10 and 100 mA cm⁻², respectively. Excellent performance of Co₃Fe₁-LDH/rGO/NF is due to the nanosheet arrays structure with open channels, synergistic coupling between Co₃Fe₁-LDH and rGO enhancing electrical conductivity, and in-situ growth of Co₃Fe₁-LDH on rGO/NF enhancing stability.

通过柠檬酸辅助水相共沉淀策略合成了在 rGO（还原氧化石墨烯）均匀改性的镍泡沫上原位生长的新型 CoFe-LDH（层状双氢氧化物）纳米片阵列。系统表征表明 Co _x Fe ₁ -LDH/rGO/NF (x = 4, 3, 2) 系列均显示 Co _x Fe ₁ -LDH 纳米片 (150–180 × 15 nm) 在 rGO 表面垂直生长/NF。特别是，Co ₃ Fe ₁ -LDH/rGO/NF 表现出最佳性能，在 10 mA cm ^{-2 下的}过电位为 250 和 110 mV在 1 M KOH 中分别用于析氧反应 (OER) 和析氢反应 (HER)。当它同时用作阴极和阳极以进行整体水分解时，它们在 10 和 100 mA cm ^{-2 下}分别需要 1.65 和 1.84 V。Co ₃ Fe ₁ -LDH/rGO/NF 的优异性能归因于具有开放通道的纳米片阵列结构、Co ₃ Fe ₁ -LDH 和 rGO之间的协同耦合增强导电性以及 Co ₃ Fe ₁ - 的原位生长rGO/NF 上的 LDH 增强稳定性。