▎ 摘　　要

Ultrathin graphene oxide@polypyrrole-1 (GO@PPy-1) nanosheets are successfully prepared by in situ chemical oxidative polymerization of pyrrole using GO/FeCl3 complexes as the oxidant and template. Pyrrole nanolayers are homogeneously coated on the GO, and both the inner and outer layer monomer can be oxidized by the free Fe3+ ions. The GO@PPy-1 exhibited higher areal specific capacitance (1532 mF cm(-2) at 0.88 mA cm(-2)), better rate capability (capacitance retention rate of 41% from 0.88 to 44 mA cm(-2)) and excellent cycling stability (less than 10% capacity loss after 1000 cycles) in a three-electrode workstation. More important, the GO@PPy-1 assembled solid-state symmetrical supercapacitor showed high energy density of 114 mu Wh cm(-2) at a power density of 500 mu W cm(-2) and high power of 20,000 mu W cm(-2) at an energy density of 70 mu Wh cm(-2). The superior capacitive behavior could be attributed to the thinner PPy capping layer on the surface of GO. In addition, GO-grafted PPy can prevent the exfoliation of PPy during the charge-discharge process. Furthermore, the GO@PPy-1 showed better electrochemical performance compared to the GO@PPy-2 synthesized by the conventional way. The simple method opens up a new route to large-scale prepare graphene based conducting polymer materials for applications in supercapacitors.