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

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. (C) 2018 Elsevier B.V. All rights reserved.