Importance of carbon quantum dots for improving the electrochemical performance of MoS2@ZnS composite

In order to improve the electrochemical properties of MoS2, an important method of reflecting synergy between different components has been proposed. And this article describes that four kinds of electrode materials were prepared using a simple hydrothermal method. Herein, a composite doping a small amount of carbon quantum dots (CQDs) can be used as an excellent electrode material. It can be found that carbon quantum dots/MoS2@ZnS composite (CQDs/MoS2@ZnS composite) possesses a higher specific capacitance of 2899.5 F g(-1) than MoS2@ZnS composite (2176.1 F g(-1)), single MoS2 (1067.6 F g(-1)) and single ZnS (423.4 F g(-1)). Moreover, CQDs/MoS2@ZnS has excellent cycling stability, maintaining 76.1% of original capacitance after 3500 cycles. The results indicate that the CQDs/MoS2@ZnS composite electrode has potential application in supercapacitors, and the investigation also provides an important idea to improve electrochemical performance of other electrode materials through doping a small amount of CQDs.