Preparation and Photocatalytic Properties of Ceramic Nanocomposites Added Zinc Sulfide Nanoparticles

Abstract

We fabricated ceramic ZnS nanocomposites by mixing fly ash of a thermal power plant and waste glass powder with ZnS nanoparticles manufactured by a template-free hydrothermal treatment method. Ceramic ZnS nanocomposites with structure and mechanical properties produced using powder mixtures were obtained by applying milling and annealing procedures at a heat treatment temperature of 700 °C. Its photocatalytic activity was evaluated with methyl orange (MO), acetaldehyde (ATA), 2,4-dichlorophenoxyacetic acid (2,4-D), and methylene blue (MB) as photodegradation targets. Crystallization behavior of ceramic ZnS nanocomposites prepared in this study was examined through X-ray diffraction (XRD) analysis and surface morphological observation. Chemical composition of the ceramic ZnS nanocomposites was estimated using field emission-scanning electron microscopy (FE-SEM) and energy dispersive X-ray spectrometry (EDS). Its physicochemical properties were characterized by measuring density, compressive strength, bending strength, and chemical durability according to ZnS nanoparticle content. Results confirmed that addition of ZnS nanoparticles significantly improved physicochemical properties of the prepared nanocomposite samples. As the content of ZnS nanoparticles increased, photocatalytic activity of ceramic ZnS nanocomposites with and without acid treatment for photodegradation target material also increased under UV light irradiation. Degrees of photocatalytic degradation of MO, ATA, 2,4-D, and MB by ceramic ZnS nanocomposites added with 20 wt% ZnS nanoparticles (after immersion in acidic solution) were about 0.285, 0.118, 0.280, 0.256 after UV irradiation for 180 min, respectively. Moreover, the photocatalytic degradation rate of target substances for photodegradation was estimated using pseudo-first-order kinetics proposed by Lagergren.