氧化石墨烯/聚吡咯插层复合材料的制备和电化学电容性能

Preparation and Electrochemical Capacitance Properties of Graphene Oxide/Polypyrrole Intercalation Composite

以FeCl3-甲基橙(MO)为模板,通过化学原位聚合法成功制备出氧化石墨烯/聚吡咯(GO/PPy)插层复合材料.采用X射线衍射(XRD)、傅里叶变换红外(FTIR)光谱、扫描电镜(SEM)和透射电镜(TEM)等测试技术对复合材料进行物性表征.此外,利用循环伏安、恒电流充放电和交流阻抗测试方法对复合材料在两种不同水系电解液(1mol·L-1Na2SO4和1mol·L-1H2SO4)中的电化学性能进行了研究.结果显示:氧化石墨烯和聚吡咯表现出各自优势并发挥协同作用,使得GO/PPy插层复合材料在中性和酸性电解液中都显示出可观的比电容.电流密度为0.5A·g-1时,GO/PPy插层复合材料在Na2SO4和H2SO4电解液中的比电容分别为449.1和619.0F·g-1,明显高于纯PPy的比电容.经过800次循环稳定性测试后,两种不同电解液中,复合材料初始容量的保持率分别为92%和62%.其中酸性电解液体系中初始容量更大,而中性溶液中具有更稳定的循环性能.

Graphene oxide/polypyrrole （GO/PPy） intercalation composite was successfully prepared via in-situ chemical oxidative polymerization of pyrrole monomers by using methyl orange （MO） as a template agent. The morphology and microstructure of the composite were characterized by X-ray diffraction （XRD） analysis, Fourier transform infrared （FTIR） spectroscopy, scanning electron microscopy （SEM）, and transmission electron microscopy （TEM）. In addition, the electrochemical properties of the composite material were investigated by cyclic voltammetry （CV）, galvanostatic charge/discharge and electrochemical impedance spectroscopy techniques in two different aqueous electrolytes （1 mol·L^-1 Na2SO4 and 1 mol·L^-1 H2SO4）. The results indicated that the GO/PPy intercalation composite displayed considerable specific capacitance in both neutral and acid electrolytes, which is attributed to taking full advantage of the superior properties and synergy of graphene oxide and polypyrrole. The GO/PPy intercalation composite exhibited the specific capacitance of 449.1 and 619.0 F·g^-1 in the Na2SO, and H2SO4 electrolytes, respectively, at a current density of 0.5 A·g^-1. This is significantly higher than the corresponding specific capacitance of pure PPy. After 800 cycling test, the specific capacitance of the composite remained about 92% and 62% of the initial capacitance in the two different electrolytes, respectively. A higher initial capacitance was obtained in the acidic electrolyte, but the composite showed better electrochemical cyclic stability in the neutral electrolyte.