电沉积原位生长Co₃O₄电催化剂的构建及其析氧性能研究

Fabrication of in Situ Electrodeposited Co₃O₄ Electrocatalyst and Study of Its Oxygen Evolution Performance

摘要: 开发高性价比、低过电位的酸性耐用的OER电催化剂以提高电催化整体能量转换效率的问题仍然具有挑战性。过渡金属氧化物因储量丰富、电子结构可调而备受关注。在此，我们研究了电沉积溶液浓度、沉积时间及退火温度等关键工艺参数对Co₃O₄形貌演变、电子结构调控及OER性能的影响，确立了最优的电沉积–退火合成策略。电沉积原位生长自支撑Co₃O₄前驱体与空气氛围退火处理诱导了纯相尖晶石Co₃O₄的形成。XPS与XAFS分析表明，优化退火条件导致Co³⁺位点含量增加，Co³⁺的含量与OER活性呈正相关。近边结构分析揭示了氧空位的生成。这些缺陷位点与优化的电子结构共同构成了提升OER本征活性的内在因素。成功构建了形貌可控、电子结构优化的Co₃O₄/碳布自支撑电极。优化的Co₃O₄电催化剂具有优异的酸性稳定性(19 h)和较低的过电位(365 mV)，在钴基尖晶石材料的电催化OER应用中具有广阔的前景，为设计高性能非贵金属电催化剂提供了重要参考。

Abstract: The development of cost-effective, low-overpotential, and acid-stable OER electrocatalysts to enhance overall energy conversion efficiency remains a significant challenge. Transition metal oxides have attracted considerable attention due to their abundant reserves and tunable electronic structures. In this study, we systematically investigated the effects of key process parameters—such as electrodeposition solution concentration, deposition time, and annealing temperature—on the morphological evolution, electronic structure regulation, and OER performance of Co₃O₄, establishing an optimal electrodeposition-annealing synthesis strategy. In situ electrodeposition growth of self-supported Co₃O₄ precursors followed by annealing in an air atmosphere induced the formation of a pure-phase spinel Co₃O₄. XPS and XAFS analyses revealed that optimized annealing conditions led to an increased content of Co³⁺ sites, and the Co³⁺ content showed a positive correlation with OER activity. Near-edge structure analysis indicated the generation of oxygen vacancies. Through systematic optimization of synthesis parameters, a self-supported Co₃O₄/carbon cloth electrode with controllable morphology and optimized electronic structure was successfully constructed. Consequently, the optimized Co₃O₄ electrocatalyst exhibits excellent acid stability (19 h) and a low overpotential (365 mV), demonstrating great promise for OER electrocatalysis in cobalt-based spinel materials and providing an important reference for the design of high-performance non-noble metal electrocatalysts.