A ZnO-MnO composite was synthesized using a simple solvothermal method combined with a high-temperature treatment. To observe the phase change during the heating process, in situ high-temperature XRD analysis was performed under vacuum conditions. The results indicated that ZnMn<inf>2</inf>O<inf>4</inf> transformed into the ZnO-MnO composite phase starting from 500 °C and that this composite structure was retained until 700 °C. The electrochemical performances of the ZnO-MnO composite electrode were evaluated through galvanostatic discharge-charge tests and cyclic voltammetry analysis. Its initial coulombic efficiency was significantly improved to 68.3% compared to that of ZnMn<inf>2</inf>O<inf>4</inf> at 54.7%. Furthermore, the ZnO-MnO composite exhibited improved cycling performance and enhanced rate capability compared with untreated ZnMn<inf>2</inf>O<inf>4</inf>. To clarify the discharge-charge mechanism of the ZnO-MnO composite electrode, the structural changes during the charge and discharge processes were also investigated using ex situ XRD and TEM.
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Physics and Astronomy(all)