Studies on the Preparation of ZnMn2O4and Its Electrochemical Performance
|School||Huazhong University of Science and Technology|
|Keywords||lithium-ion battery anode material ZnMn2O4 hydrothermal template|
Spinel structure ZnMn2O4is an important inorganic functional semiconductormaterial, and it has well research value and applied foreground in areas such asbiomedical, sensor, catalyst, battery materials, and so on. As an anode material forlithium-ion battery, ZnMn2O4has attracted more and more material scientists’ attentionfor its prominent advantages such as high theory specific capacity, low price,environmental friendly, and so on. But it has poor rate capability and cyclability for itslow conductivity and big volume expansion. Now scientists are trying to improve itselectrochemical performance by reducing the particle size and building new morphologyand structure and have obtained some progresses.In this paper, ZnMn2O4was prepared by hydrothermal, template method, ureacombustion method and coprecipitation method. The effects of different binder on itselectrochemical performance were studied. Based on the coprecipitation method, weconduct conducting polymer PPy coating. The thermal stability、 compositionmicrostructure and morphology of materials were characterized all kinds of methods suchas TG-DTA、XRD、SEM、 TEM、XPS, and so on. The electrochemical performance wasinvestigated by CV and galvanostatic charge-discharge cycling test.The results show that ZnMn2O4with partical size of20nm can be successfullyprepared by hydrothermal reaction. And water-soluble binder CMC-SBR has largelyimproved the performances of ZnMn2O4. Hollow porous submicron-sized ZnMn2O4spheres composed of primary particles with diameters of25-50nm have beensuccessfully prepared using self-made MnCO3spheres as template. The hollow poroussphere structure is beneficial for improving the cyclability and rate capability ofZnMn2O4. The synthesis temperature of urea combustion method is very low, but therepeatability is poor. Conducting polymer PPy coating didn’t improve the electrochemicalperformance, which may be related to the inappropriate base materials.