Low cost electrochemical composite material of paper cup waste carbon (P-carbon) and Fluorescein for supercapacitor application

Waste paper cups were employed as a source of carbon (P-carbon). Fluorescein molecules were immobilized on this carbon surface. The composite P-carbon/Fluorescein was investigated as an alternative supercapacitor material. The structure and properties of the synthesized materials are confirmed by some characterization techniques like XRD, SEM, EDX, UV and TGA. The functional group present in the material was confirmed by FT-IR and Raman spectral studies. The electrochemical behaviour of the material was analysed by Cyclic Voltametery (CV), Galavanostatic charge discharge (GCD) and Electrochemical Impedance Spectroscopy (EIS) studies. Organic compound DFT calculation was carried out for the immobilized organic compound to evaluate the theoretical band gap energy. The synthesized electro active composite P-carbon/Fluorescein shows an excellent capacitance value of 214 Fg−1 when compared to the individual materials P-carbon and Fluorescein, and it exhibited a good cyclic stability till 1000 cycle of charge discharge study. The study throws light on the fact that waste carbon materials can be modified for energy storage applications.