Photodegradation of Methylene Blue and Rhodamine B Using Laser-Synthesized ZnO Nanoparticles

Abstract

In this paper we examined the photocatalytic efficiency of a laser-synthesized colloidal solution of ZnO nanoparticles synthesized by laser ablation in water. The average size of the obtained colloidal ZnO nanoparticles is about 47 nm. As revealed by electron microscopy, other nanostructures were also present in the colloidal solution, especially nanosheets. A photocatalytic degradation of UV-irradiated Methylene Blue and Rhodamine B solutions of different concentration in the presence of different ZnO catalyst mass concentrations was studied in order to examine their influence on photodegradation rates. ZnO nanoparticles have shown high photocatalytic efficiency, which is limited due to different effects related to UV light transmittivity through the colloidal solution. Therefore, increasing catalyst concentration is effective way to increase photocatalytic efficiency up to some value where photodegradation rate saturation occurs. The photodegradation rate increases as the dye concentration decreases. These findings are important for water purification applications of laser-synthesized ZnO nanoparticles.

Statistical modeling of methylene blue degradation by yeast-bacteria consortium; optimization via agro-industrial waste, immobilization and application in real effluents

“…The experiments were performed in triplicate and the average was considered. The discoloration efficiency was calculated based on the following equation [ 44 ]: …”

A comparison between thermal lens and conventional optical spectroscopy for monitoring of a photocatalytic process

“…Methylene blue photodegradation using different photocatalysts has been widely studied [18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35]. A solution of 1 ppm of methylene blue in water was placed into a measurement cell in contact with the ZnO film catalyst, which was irradiated with the lamp light.…”

Green Synthesis, Structural Characterization and Photocatalytic Applications of ZnO Nanoconjugates Using Heliotropium indicum

“…Among the various approaches to synthesis NPs, plants seem to be the best candidates due to their easy availability, low cost, low toxicity, and capacity for large-scale synthesis of stable, controlled sized and shaped NPs. Moreover, plant extracts naturally act as a reducing, stabilizing, and capping agent for the synthesis of NPs [7,21,32,48].…”

“…The resulting spectra are depicted in Figure S4. The phytochemicals present in these extracts are considered to provide the action of capping, and stabilizing agents that aid the formation of ZnO NPs [7,21,32,48]. Substance-specific vibrations of the molecules lead to the specific signals obtained by IR spectroscopy in the range of 400-4000 cm −1 .…”