Starch-assistant synthesis of Ni quantum dots/ultrathin carbon nanosheet hybrids for high performance supercapacitor

Abstract

Ultrathin carbon nanosheet-supported Ni quantum dot hybrids (C-Ni-QDs) were synthesized via a two-step process. The obtained hybrid materials exhibited high specific capacitance of 1120 F g−1 at 2 A g−1 and excellent rate capability with a retention ratio of 81.3% at 20 A g−1. Besides, the C-Ni-QDs hybrids also exhibited outstanding cycling stability with a capacitance retention of 97.0% after 2000 cycles. These results indicated that C-Ni-QDs hybrids could be a promising material for supercapacitors.