Green synthesis of ZnO nanoparticles using Carica papaya leaf extracts for photocatalytic and photovoltaic applications

We report a facile synthesis of hexagonal wurtzite ZnO nanoparticles through green synthesis method using Carica papaya leaf extract. To understand the structural phase purity, morphology and size, the sample was characterized through various analytical techniques. The obtained results reveal that the synthesized ZnO nanoparticle is a phase pure hexagonal wurtzite structure in spherical shape with particle size of similar to 50 nm. Furthermore, the synthesized ZnO nanoparticles were used as photocatalyst as well as photo anode for methylene blue dye degradation and dye sensitized solar cells, respectively. It was found that the synthesized ZnO nanoparticles completely degrade the methylene blue dye within 180 min under UV light irradiation. In addition, it shows an energy conversion efficiency of 1.6% with a current density of 8.1 mA cm(-2) in dye sensitized solar cells.