Structural, morphological and optical characteristics of ZnO particles synthesized in the presence of surfactants CTAB and Pluronic F-127

Abstract

Due to its optical and electrical properties, low toxicity, chemical and physical stability, as well as inexpensiveness, zinc oxide (ZnO) based materials have a great potential to be used as photoelectrode in photo(electro)catalysis. Photo(electro)catalytic activity of ZnO materials can be improved by modification of particles morphology and surface topology. In this work, the influence of two different surfactants: cetyltrimethylammonium bromide (CTAB) and Pluronic F-127, on the crystal structure, morphology, optical and photo(electro)catalytic properties of ZnO particles, were examined. ZnO powders were synthesized by microwave processing of a precipitate which was previously prepared by "drop by drop" method in the presence of the surfactants. The crystal structure and phase purity of the ZnO particles were determined by X-ray diffraction and Raman spectroscopy. The effects of the surfactants on ZnO particles morphology were examined by the field emission scanning electron microscopy (FE-SEM). The optical properties were studied using UV-Vis diffuse reflectance and photoluminescence spectroscopy. Photocatalytic activity was examined via decolorization of methylene blue under direct sunlight irradiation. It was found that synthesized ZnO powders have a significant photocatalytic activity. Electrochemical properties were studied using linear sweep voltammetry and impedance spectroscopy in Na2SO4 electrolyte. ZnO powder synthesized in the presence of CTAB (ZnO/CTAB) showed the most significant reduction of potential and the fastest kinetic of oxygen evolution.