Synthesis and application of multiple rods gold–zinc oxide nanostructures in the photocatalytic degradation of methyl orange

Abstract

Zinc oxide and gold-zinc oxide (Au-ZnO) nanostructures with multiple rods (multipods) morphology were successfully prepared. Au-ZnO nanostructures were synthesized via a simple precipitation route method in the presence of oligoaniline-coated gold nanoparticles. The Au-ZnO catalyst obtained was applied for the degradation of methyl orange in an aqueous solution under UV irradiation. Effects of the operational parameters such as the solution pH, amount of photocatalyst, and dye concentration on the photocatalytic degradation and decolorization of methyl orange were studied. Detailed studies including kinetic study and regeneration of catalyst were carried out on the optimal conditions for the photodegradation of methyl orange by Au-ZnO multipods in aqueous solution. Effect of foreign species on the photodegradation of methyl orange was also studied. An enhancement of the photocatalytic activities for photodegradation of methyl orange was observed when the gold nanoparticles were loaded on the zinc oxide multipods. The proposed catalyst was applied for the degradation of methyl orange in synthetic wastewater samples with satisfactory results.

Synthesis of PEDOT/ZnO Photocatalyst: Validation of Photocatalytic Activity by Degradation of Azo RR45 Dye Under Solar and UV-A Irradiation

“…Morphology of pure PEDOT polymers differ among themselves as it is observed that polymers form the aggregated particles. The size of primary particles seems to be larger for PEDOT (1)(2)(3)(4)(5) (Fig. 6c) than that of the other two samples PEDOT (1-2) (Fig.…”

“…8, inset) which is characteristic of pure PEDOT and confirms its amorphous nature 40 . That peak appears for samples with higher concentration of polymer in composite, PEDOT/ZnO (1-3) and (1)(2)(3)(4)(5). The XRD results show that the increase in the polymer ratio in composite significantly affects the surface of ZnO photocatalyst.…”

“…Thus, in order to avoid the negative environmental impact by discharge of such wastewaters, an efficient treatment is required. Azo dyes are considered non-degradable, and common degradation processes such as physicochemical treatment, oxidative techniques and other are not able to completely remove dyes from the contaminated wastewaters 3 . Heterogeneous photocatalytic oxidation process is promising for removal of synthetic dyes during wastewater treatment [4][5][6] .…”

Adsorptive Removal of a Reactive Azo Dye Using Polyaniline-Intercalated Bentonite

“…The constant is given as: (15) …where c 0 (mg/L) is the initial RR-2 concentration and b (L/mg) is the Langmuir constant. Fig.…”

“…Therefore, physical and chemical methods, including coagulation [9], adsorption [10][11] membrane filtration [12][13], and advanced oxidation [14][15] are employed to treat dye wastewater. Among these techniques, adsorption is attracting increasing interest due to its properties of simple operation, high performance, and low running cost [16][17].…”