Highly efficient and stable electrocatalysts for oxygen evolution reaction are of technological importance in energy conversion and storage. Surface modification is one of the most promising strategies for improving the activity of such electrocatalysts. Herein, we report the multilayer hollow MnCo₂O₄ microsphere enriched with oxygen vacancies induced by the plasma-engraving technique for the first time. The defective MnCo₂O₄ microsphere exhibits an excellent catalytic activity and durability as compared to pristine MnCo₂O₄. Our electrochemical analysis, combined with first-principles calculations, reveals that the improved electrocatalytic performance is attributed mainly to abundant active sites after the plasma treatment and the effects of the introduced oxygen vacancies. The oxygen vacancy not only reduces the density of states near the Fermi level but also lowers the Co d-band center_, weakening the adsorption of the intermediates. This facilitates the desorption of the adsorbates, which is necessary for oxygen evolution reaction.

用于氧释放反应的高效，稳定的电催化剂在能量转换和存储中具有重要的技术意义。表面改性是改善此类电催化剂活性的最有希望的策略之一。在这里，我们首次报道了多层中空的MnCo ₂ O ₄微球，该球富含等离子刻蚀技术产生的氧空位。与原始的MnCo ₂ O ₄相比，有缺陷的MnCo ₂ O ₄微球表现出优异的催化活性和耐久性。。我们的电化学分析，结合第一性原理计算，发现改进的电催化性能主要归因于等离子体处理后的丰富活性位和引入的氧空位的影响。氧空位不仅降低了费米能级附近的态密度，而且降低了Co d能带中心_，削弱了中间体的吸附。这有利于被吸附物的解吸，这是析氧反应所必需的。