γ-MnO2 nanorod-assembled hierarchical micro-spheres with oxygen vacancies to enhance electrocatalytic performance toward the oxygen reduction reaction for aluminum-air batteries

• 来源期刊: 能源化学
• 年，卷（期）: 2020,（12）
• 页码范围: 81-89
• 页数: 9页
• 语种: 英文

摘要

γ-MnO2 nanorod-assembled hierarchical micro-spheres with abundant oxygen defects are synthesized by a simple thermal treatment approach as oxygen reduction electrocatalysts for Al(aluminum)-air batteries.The rich oxygen vacancies on the surface of γ-MnO2 are verified by morphology,structure,electron paramagnetic resonance(EPR)and X-ray photoelectron spectroscopy(XPS)results.The oxygen reduction reaction(ORR)electrocatalytic activity of γ-MnO2 is significantly improved by the incoming oxygen vacancies.The γ-MnO2 nanorod-assembled hierarchical micro-spheres calcined under 300 ℃ in Ar atmosphere show the best ORR performance.The primary Al-air batteries using γ-MnO2 catalysts as the cathode,which demonstrates excellent peal power density of 318 mW cm-2 when applying theγ-MnO2 catalysts with optimal amount of oxygen vacancies.