MnO_2/石墨烯/聚噻吩复合材料的制备与充放电性能研究

Study on preparation and charge-discharge properties of MnO_2/graphene /polythiophene composites

采用原位水热氧化还原法制备了MnO2/石墨烯/聚噻吩(MnO2/G/PTh)三元复合材料.使用扫描电子显微镜和X射线衍射仪对复合材料的形貌和结晶性进行了表征,运用电池测试系统考察了材料的充放电性能.结果表明,复合材料中石墨烯表面有球状MnO2生长,大颗粒聚噻吩的缝隙中也存在有球状MnO2.合成的MnO2/G/PTh复合材料,经过20次循环后电极材料的比容量基本都能保持在300 mAh/g左右,其中组比为20∶1∶0.67的复合材料首次充放电效率达到46.5%,放电容量最高.MnO2/G/PTh复合材料的充放电稳定性及库伦效率均高于MnO2.

The MnO2/graphene /polythiophene composites were synthesized by in-situ hydrothermal oxidation-reduction method. The morphology and crystallinity of the composites were characterized with scanning electron microscope（ SEM） and X-ray diffraction spectroscopy（ XRD）. The electrochemical chargedischarge performance of the nanocomposites was tested by the battery test system. The results showed that globulg MnO2 was grown both on the surface of graphene and the gap of large particles of polythiophene in the nanocomposites. The specific capacity of synthesized MnO2/G /PTh composites was 300 mAh /g after the cycle of 20 times,the first charge and discharge efficiency of the nanocomposites with the ratio of 20∶1∶0. 67 was 46. 5%,the discharge capacity was the highest. The charge-discharge stability and coulombic efficiency of the MnO2/graphene /polythiophene nanocomposites were better than that of pristine MnO2.