Comparative Study of Green Nano Synthesis of Versatile TiO2 with its Chemical Nano Synthesis – Application to Photocatalytic and Antibacterial Activity

Background & Objective: Currently, Green synthesis/biosynthesis is a rapidly growing, advantageous method for nanoparticle synthesis and it inculcates interest among researchers. It has its own significance in the field of biomedical, industrial, pharmaceutical and other fields of science and technology. TiO2 has inimitable properties in the field of pharmaceutical/biomedical and industrial applications. Hence, the present facile study proposed to deal with the synthesis of TiO2 nanoparticles (NPs) through the chemical method and the green method. The synthesized samples are compared to prove the suitable methodology for synthesizing TiO2 nanoparticles (NPs). 
Methods: The TiO2 nanoparticles were synthesized through a sophisticated chemical method. The green/biosynthesis of TiO2 nanoparticles was carried out using AdathodaVasica, Acalypha Indica and Annona squamosa leaf extract. Using the synthesized samples, the structural, morphological, optical, surface and antibacterial characteristics of synthesized nanoparticles were investigated using FTIR, XRD, EDAX, UV, PL, SEM and antibacterial analysis. 
Result: The FTIR spectra reveal the presence of a Ti-O bond. The structural characterization using XRD analysis confirms the crystalline size at the nano level. The bandgap energies were calculated through the UV spectrum and the photocatalytic behaviour of the TiO2 nanoparticle is further confirmed by the photoluminescence study. The SEM analysis pictures the morphology of TiO2 NP. The antibacterial study manifests the larger region of inhibition for the TiO2 NP obtained from the leaf extract. The results of the samples were compared and identified their efficiency. 
Conclusion: From the studies, it concludes that the green synthesized NPs are much more efficient than the chemically prepared sample. The green synthesized TiO2 NP is much more active than that obtained from the chemical method. The green synthesized TiO2 nanoparticles are more suitable for both industrial/photocatalytic and pharmaceutical applications.