Synthesis and supercapacitive behaviour of SnO 2 /r-GO nanocomposite

In this work, we have used Camellia sinensis leaves extract in the synthesis of SnO 2 NPs. The biologically synthesised SnO 2 NPs were combined with reduced graphene oxide (r-GO) to produce SnO 2 /r-GO under ultrasonic conditions. The extract-based synthetic method was found to be environmentally safe, less time-consuming, and efficient. According to phyto-chemical screening, the biologically active components such as terpenoids, phyto-sterols, carbohydrates, amino acids, alkaloids, tannins, and flavonoids, respectively, were present in Camellia sinensis leaves extract. Various analytical techniques have been used to investigate the SnO 2 /r-GO. FTIR analysis indicated the presence of O-H, C C, Sn-O, Sn-C, etc. bonds on the surface of green and ultrasonically based SnO 2 /r-GO. The crystalline nature of SnO 2 /r-GO has been confirmed by XRD pattern. Further, the freshly synthesised SnO 2 /r-GO has been utilised as a supercapacitor material. The specific capacitances of the cost-effective SnO 2 /r-GO were found to be 310.7 F g −1 at an initial scan rate (10 mV s −1 ) and 267.8 F g −1 at an initial current density (1 A g −1 ), respectively. The specific energy and specific power were evaluated as 13.3 Wh kg −1 and 160.6 W kg −1 at 1 A g −1, and 4.6 Wh kg −1 and 1606.2 W kg −1 at 10 A g −1, respectively.