Self-assembled PANI/CeO2/Ni(OH)2 hierarchical hybrid spheres with improved energy storage capacity for high-performance supercapacitors

Abstract

PANI/CeO2/Ni(OH)2 hierarchical hybrid spheres were successfully prepared by a simple one-step self-assemble reaction. The structure and morphology characterization revealed the hybrid spheres were constructed with self-assembled nanosheets. The formation mechanism of the hierarchical structure was discussed. N2 adsorption–desorption isotherms showed that the PANI/CeO2/Ni(OH)2 had improved specific surface area. Under optimized conditions, the PANI/CeO2/Ni(OH)2 hierarchical hybrid spheres showed highly electrochemical activity and supercapacitor performance compared with Ni(OH)2 and CeO2/Ni(OH)2. The max specific capacitance reached to 2556 F g−1. It was still as high as 2130 F g−1 even at the high current density, showing good rate capability. After 1000 cycles continuous charge–discharge process, the hybrid sphere can retain 95.9% of its initial capacitance, indicating good cycle stability. The asymmetric specific capacitance can be of 348 F g−1 and the capacity retention rate can hold 80.4% after 8000 cycles. Such high performance of PANI/CeO2/Ni(OH)2 hybrids may have potential practical application value used in supercapacitors.