Organic-inorganic nanocomposites of (2-hydroxypropyl) cellulose as a precursor of nanocrystalline zinc oxide layers

The sol-gel method of synthesis of the hybrid nanocomposite films of ZnO/(2-hydroxypropyl) cellulose (HPC) on silica glass is presented. The sol phases were prepared for different weight ratios of zinc acetate dihydrate to HPC in the presence of triethylamine (TEA). Raman spectrum of the mixture of ZnAc and HPC indicates coordinating interaction between zinc ion and HPC. The generation of ZnO nanoparticles in the HPC matrix proceeds in situ through the annealing of the gel phase at a temperature of 160 degrees C. Identification of ZnO nanoparticles in the HPC matrix is done by using photoluminescence (PL), UV-Vis, and Raman spectroscopy. The films of ZnO/HPC nanocomposite are transparent in the visible light and show a higher energy value of absorption edge compared with ZnO in the bulk. Nanocrystalline films of ZnO were obtained by the calcination of ZnO/HPC nanocomposite at 500 degrees C. ZnO films possess a good transparency for the visible light and high absorbance for UV light. Nanocrystallite sizes of ZnO particles were estimated from the Xray lines broadening. The properties of ZnO layers were studied by the evaluation of PL, X-ray investigation and atom force microscope (AFM) scanning, and the optical absorption edge. Copyright (C) 2008 John Wiley & Sons, Ltd.