Novel Green Route of Synthesis of ZnO Nanoparticles by Using Natural Biodegradable Polymer and Its Application as a Catalyst for Oxidation of Aldehydes

AbstractZnO nanoparticles have been synthesized by using biodegradable natural biopolymer viz. Gum Tragacanth. This single step approach is very cost effective and reproducible. The reaction time and concentration of precursor zinc acetate play a major role in the nature and growth of ZnO nanoparticles. ZnO nanoparticles were characterized by X-ray diffraction, SEM, FTIR, EDAX, UV-visible spectroscopy and TEM. ZnO nanoparticles with 20-30 nm in diameter and hexagonal morphology were found; dispersed uniformly. Raman spectrum shows the mode E2 high at 437 cm−1 that is related to the vibration of wurtzite Zn-O bond in crystal structure of ZnO. The space between adjacent lattice fringes is ∼ sharp 2.42 Å. UV-visible absorption spectrum shows the sharp absorption band at 308 nm assigned to the intrinsic transition from valance band to conduction band. The ZnO nanoparticles display superior catalytic activity of conversion of aldehyde to acid as compared to bulk-ZnO material, because of high surface area of ZnO nanoparticles. A trace amount of ZnO nanoparticles catalyst required for organic conversion. The ZnO nanoparticles as catalyst are highly stable, recyclable and efficient in its activity.Keywords: catalystgum tragacanthoxidationZnO nanoparticles AcknowledgmentsWe also thank National Chemical Laboratory and C-MET, Pune, India for performing analysis. The authors are very much thankful to Prashant B. Lihitkar, Sushma Petkar and Pavan Kumar for valuable suggestions.FundingWe sincerely acknowledge financial support from UGC, Nowrosjee Wadia College, Pune; BCUD, Pune University; Indian Academy of Science, Bangalore and Symbiosis Institute of Technology. Authors are thankful to ISRO for providing financial assistance.