Green synthesis is a simple, eco-friendly and emerging approach of synthesizing CeriaZirconia nanocomposites (CZ NCs) and evaluates its performance for the photocatalytic treatment of industrial waste water. Ceria-Zirconia NCs were synthesized using leaf extracts of Jatropha gossypiifolia L. for the application towards photocatalytic degradation of Brilliant Green (BG) dye under visible light irradiation. The Ceria-Zirconia NCs were characterized by Fourier Transform Infrared (FT-IR) spectrometer, UV-Visible spectrophotometer, X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM) equipped with Energy Dispersive X-ray Spectroscopy (EDX). FT-IR spectra indicate the presence of amino, carboxyl and hydroxyl functional groups on the crystal surface of the nanocomposites. In UV-Visible spectra, the nanocomposites exhibit the highest absorbance at about 252 and 340 nm. From XRD, the average crystallite size of the CeriaZirconia NCs were found to be 80.36nm, while SEM images showed the spherical clusters of agglomerated nanocomposites. The elemental composition and the purity of the nanocomposites were confirmed by Energy Dispersive X-ray Spectroscopy. The superior antifungal activity was investigated against with the fungal strains Candida albicans, Aspergillus niger and penicillium.