title: Blue emitting ZnO nanostructures grown through cellulose bio-templates.
abstract: This paper presents a green and cost-effective recipe for the synthesis of blue-emitting ZnO nanoparticles (NPs) using cellulose bio-templates. Azadirachta indica (neem) leaf extract prepared in different solvents were used as biological templates to produce nanostructures of wurtzite ZnO with a particle size ~12-36 nm. A cellulose-driven capping mechanism is used to describe the morphology of ZnO NPs. The scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infra-red (FTIR) and photoluminescence (PL) studies showed that solvents affect the growth process and the capping mechanism of bio-template severely. Structural changes in ZnO NPs were evident with variation in pH, dielectric constants (DC) and boiling points (BP) of solvents. Furthermore, an energy band model is proposed to explain the origin of the blue emission in the as-obtained ZnO NPs. PL excitation studies and the theoretical enthalpy values of individual defects were used to establish the association between the interstitial-zinc-related defect levels and the blue emission. Copyright © 2015 John Wiley & Sons, Ltd.
authors.affiliation: Govt. V.Y.T. PG., Autonomous College, Durg (C.G.), India.
authors.forename: Anjali
authors.initials: A
authors.lastname: Oudhia
authors.affiliation: Govt. V.Y.T. PG., Autonomous College, Durg (C.G.), India.
authors.forename: Savita
authors.initials: S
authors.lastname: Sharma
authors.affiliation: Govt. V.Y.T. PG., Autonomous College, Durg (C.G.), India.
authors.forename: Pragya
authors.initials: P
authors.lastname: Kulkarni
authors.affiliation: Department of Physics, BIT, Durg (C.G.), India.
authors.forename: Rajesh
authors.initials: R
authors.lastname: Kumar
mesh_terms: D031601:Azadirachta / Q000737:chemistry; D002482:Cellulose / Q000737:chemistry*; D003116:Color; D049449:Luminescence; D049329:Nanostructures / Q000737:chemistry*; D010316:Particle Size; D010936:Plant Extracts / Q000737:chemistry; D012997:Solvents / Q000737:chemistry; D013499:Surface Properties; D015034:Zinc Oxide / Q000138:chemical synthesis / Q000737:chemistry*
chemical_list: D010936:Plant Extracts; D012997:Solvents; D002482:Cellulose; D015034:Zinc Oxide
keywords: bio-templates; intrinsic defects in ZnO; nanostructures; photoluminescence