Flower-like carbon doped MoS₂/Activated carbon composite electrode for superior performance of supercapacitors and hydrogen evolution reactions

Polyethylene tetraphthalate (PET) bottles, a major environmental pollutant from the food industry, has been used as an activated carbon source in the current work. The specific surface area of the activated carbon has been analyzed using N₂ adsorption/desorption isotherms, at different sonication time periods. A high surface area of 899 m² g^-1 with microporosity has been achieved for 20 h sonication followed by activation at 800 °C. To further enhance the material performance, carbon doped MoS₂ (MoS₂–C), using conventional hydrothermal technique has been synthesized. Different composite ratios of activated carbon and MoS₂-C have been tested using electrochemical impedance spectroscopy and the best ratio owing to lesser charge-transfer resistance has been chosen for supercapacitor and HER analysis. The porous network of the plastic derived activated carbon (PAC) with a few layers of MoS₂–C contributes significantly to the increase in the power density (469 W kg^-1). By inducing defects on the material surface, there has been a significant enhancement in the electrocatalytic activity on PAC and this facilitates HER on its surface. Subsequently, the HER activity of the PDAC/MoS₂–C composite has also been reported. Here, the PDAC defective sites along with the hexagonal MoS₂–C's largely exposed reactive edges indicate a reduction in the overpotential and Tafel values of −195 mV and −82 mVdec⁻¹, suggesting that the material under investigation is a good catalyst for electrochemical HER. Also, this article reports for the first-time, HER activity of defect induced plastic derived activated carbon and its excellent catalytic activity.