Aerosol derived carbon dots decorated boron nitride supported Zn-doped MoS2 for high performing flexible asymmetric supercapacitor

Abstract

Alternative finding of toxic pollutant materials in proper utilization is a great challenge. Toxic and pollutant cigarette smoke having different π-conjugated organic components may work well as a precursor for carbon dots (CDs). In this work, cigarette smoke aerosol has been used for the synthesis of CDs and CDs have been further used for the fabrication of supercapacitor electrode. This methodology could be able to mitigate the two major problems-energy crisis and environment pollution. The smart combination of EDLC-type CDs deposited boron nitride (BN) and pseudocapacitive type Zn-doped MoS2 was able to enhance the supercapacitive performances. Heteroatom doping into MoS2 enhances the capacitive performances through the effective Faradic reactions. CDs and CDs deposited BN (CDs@BN) have been characterized using different characterization techniques. Zn-doped MoS2 has been uniformly grown on the CDs decorated BN (Zn–MoS2/CDs@BN) resulting in the stabilization of the electrode system. Zn–MoS2/CDs@BN nanohybrid delivered a specific capacitance (Sp.C) of 397 F/g in three-electrode system. Further, the asymmetric supercapacitor (ASC) device using Zn–MoS2/CDs@BN as cathode demonstrated wide potential range (up to 1.8 V) with a volumetric energy density of 3.42 mW h/cm3 and retaining a capacitance of ∼89% after 10,000 charging-discharging processes. Moreover, a flexible ASC device was made-up using viscous ionic electrolyte and it was able to glow a red LED, while it was bended in different angles. The methods described here will give a straightforward approach for using toxic-pollutant cigarette smoke to fabricate supercapacitor electrodes in order to compensate the upcoming energy crisis in a sustainable way.