The oxygen evolution reaction (OER) in acid solution is a significant challenge for non-precious metal electrocatalysts based on the transition metals although they have shown good OER performance in alkaline solution. In this study, we synthesized the electrocatalysts containing two or three Co species (Co, CoO and Co₃O₄) nanoparticles on porous graphitic carbon (PGC) nanosheets which were prepared by a facile and low-cost synthesis where Co(NO₃)₂•6H₂O and glucose were pyrolyzed in the presence of sodium chloride template. The Co₃O₄-dominated catalyst as-prepared, Co₃O₄/PGC, is OER active in acid solution (1.74 V at a current density of 10 mA cm⁻²). We identified the OER active sites in the catalyst to be the Co₃O₄ nanoparticles rather than carbon-coated Co. Through comparative studies of the varied catalysts, we also proved that Co₃O₄ is catalytically more active than Co and CoO. The Co₃O₄/PGC catalyst, however, lost almost of all its activity after 100 voltammetric cycles in the 1.2–1.8 V voltage window. When the catalyst stability was examined potentiostatically at different potentials, the catalyst showed good stability at 1.4 V. The stability study also revealed the mechanism of the catalyst instability in acid was caused by Co₃O₄ reduction below 1.4 V and by Co₃O₄ oxidation above 1.4 V. 1.4 V is therefore a unique potential where Co₃O₄ nanoparticles are neither oxidized nor reduced to be susceptible to acid dissolution.

酸性溶液中的氧释放反应（OER）对于基于过渡金属的非贵金属电催化剂是一项重大挑战，尽管它们在碱性溶液中表现出良好的OER性能。在这项研究中，我们在多孔石墨碳（PGC）纳米片上合成了包含两种或三种Co种类（Co，CoO和Co ₃ O ₄）纳米粒子的电催化剂，该催化剂通过便捷且低成本的合成方法制备，其中Co（NO ₃）在氯化钠模板存在下，将₂ •6H ₂ O和葡萄糖热解。制备的以Co ₃ O ₄为主的催化剂Co ₃ O ₄/ PGC在酸性溶液（电流密度为10 mA cm ^-2时为1.74 V）中具有OER活性。我们将催化剂中的OER活性位点确定为Co ₃ O ₄纳米颗粒，而不是碳包覆的Co。通过对各种催化剂的比较研究，我们还证明了Co ₃ O ₄的催化活性高于Co和CoO。钴₃ O ₄然而，/ PGC催化剂在1.2–1.8 V电压范围内进行100次伏安循环后几乎失去了所有活性。当在不同电位下恒电位检查催化剂稳定性时，该催化剂在1.4 V下显示出良好的稳定性。稳定性研究还表明，在1.4 V以下还原Co ₃ O ₄和由Co ₃ O ₄引起催化剂在酸中的不稳定性机理。高于1.4 V的氧化。因此1.4 V是唯一的电势，其中Co ₃ O ₄纳米颗粒既不被氧化也不被还原为易于酸溶解。