This study presents an innovative strategy for utilizing passive cigarette smoke aerosol, a common pollutant, to prepare a sustainable supercapacitor cathode. The cathode system is developed with in situ growth of carbon dots from cigarette smoke aerosol on the acid modified nanoclay (ANc), which reduces the internal resistance of layered silicates. The modified nanoclay is subsequently combined with pseudocapacitive layered MoS 2 to enhance the electrochemical performance by redox reaction during charging and discharging cycles. To achieve optimum conductivity and specific capacitance (Sp.Cp.), both carbon dots and MoS 2 loading are varied and corresponding Sp.Cp. is calculated in the three electrode and asymmetric device configuration, respectively. The successful formation of the carbon dot modified ANc based MoS 2 composite is confirmed through a combination of structural, morphological, and spectroscopic characterization techniques. Asymmetric supercapacitor devices are fabricated using the synthesized nanocomposite as the positive and graphite as the negative electrode in 1 M TEABF 4 /DMSO electrolyte. Among acid modified nanocomposites, the device containing double the quantity of MoS 2 shows a maximum Sp.Cp. of 119.7 F g −1 with 26.7 Wh kg −1 energy density and 500 W kg −1 power density at 1 A g −1 current density. Furthermore, the optimized electrode is able to illuminate red and disco LED lights, highlighting its potential application in sustainable energy storage systems. This work presents a novel approach for utilizing cigarette smoke aerosol into high performance supercapacitor electrode materials.