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.

Cutting-edge developments in zinc oxide nanoparticles: synthesis and applications for enhanced antimicrobial and UV protection in healthcare solutions

“…67 Biopolymers, such as chitosan, cellulose, and starch, have garnered signicant attention as green templates for the synthesis of ZnO NPs. 68 These naturally occurring polymers provide a biocompatible and environmentally friendly matrix for the nucleation and growth of nanoparticles. 69 Through interactions with metal ions, biopolymers facilitate the formation of ZnO NPs with controlled morphology and size distribution.…”

Synthesis, Characterization, and Three-Dimensional Structure Generation of Zinc Oxide-Based Nanomedicine for Biomedical Applications

“…The resulting product was able to perform photocatalytic degradation of methyl orange when exposed to UV irradiation. Oudihia et al [144] described a biological method in which Azadirachta indica (neem) leaves acted as cellulose biotemplates for capping in solvents during the synthesis of blue-emitting ZnO nanostructures at 12–36 nm in size. Silk fibroin fibers were also used to synthesize biotemplated, photoluminescent ZnO NPs [145].…”

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