Biosynthesis and characterization of Pt and Au-Pt nanoparticles and their photo catalytic degradation of methylene blue

A green synthesis strategy to prepare both monogeneous platinum nanoparticles (PtNps) and bimetallic heterogeneous platinum-aurum nanoparticles (PtAuNPs) using hot water extract of green tea as a reducing, stabilizing and protecting agent is reported. The nature of both PtNPs and PtAuNPs were characterized using UV/vis spectroscopy (UV–vis), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), thermal gravimetric analysis (TGA) and energy dispersive X-ray (EDX). TEM images revealed that the biosynthesis of PtNPs were in the size range of 2–4 nm and PtAuNPs in the size range of 10-40 nm and both are crystallized in face centered cubic symmetry. Photocatalytic degradation property of Pt and Pt-Au nanoparticles were investigated by degradation of Methylene blue dye under UV light irradiation. The results show that PtNps has higher activity of degradation of Methylene blue than PtAuNPs. So, this eco-friendly, simple, cost effectiveness method may be utilized for removal of waste (pollutants) of water and other industrial purposes for better environment.