Synthesizing the Composites of Graphene Oxide-Wrapped Polyaniline Hollow Microspheres for High-Performance Supercapacitors

The novel composites of graphene oxide-wrapped polyaniline (PGO) hollow microsphere have been synthesized through a facile self-assembly method. Driven by the mutual electrostatic interactions, the polyaniline (PANI) hollow microspheres prepared by a simple copper(II)-catalyzed process are fully wrapped by graphene oxide (GO) sheets. The composites with various weight feed ratios of PANI to GO sheets are also fabricated and characterized by different methods. The electrochemical tests show that the electrochemical performances of PGO composites depend largely on the mass ratios of PANI to GO sheets. Compared with the electrode materials of PANI and other PGO composites, the PGO20 composite has the highest specific capacitance of 731.2 F/g at a scan rate of 5 mV/s and good charge/discharge cycling stability (95% of the preserved capacitance is conserved after 2000 cycles). The substantially improved electrochemical performances of PGO composites are ascribed to the synergistic effects between the conductive PANI hollow microspheres and the GO sheets. The excellent electrochemical performance suggests promising application of PGO composites in high-performance supercapacitors.