Microwave-assisted green synthesis of SnO2 nanoparticles and their optical and photocatalytic properties

In this study, SnO2 has been synthesized using Andrographis Paniculata (A. Paniculata) by microwave-assisted method. It is also characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). It exhibits the tetragonal structure with average crystallite size of 27 nm. The stretching vibration peak of Sn-O-Sn is 670 cm(-1). SEM reveals the formation of nanoparticles. The bandgap was estimated by the tauc's relation as 3.52 eV from the UV-Visible (UV-Vis) spectra. Biosynthesized SnO2 nanoparticles show excellent photocatalytic activity against Congo red dye under sunlight irradiation.