Photocatalytic Activity of ZnO/Ag Nanoparticles Fabricated by a Spray Pyrolysis Method with Different O2:N2 Carrier Gas Ratios and Ag Contents

Abstract

Wastewaters of the textile industry, e.g., those generated in Gresik, Indonesia, are a possible threat to the environment and should be treated before disposal. Photodegradation is a more promising method to overcome this problem than conventional methods such as biodegradation. ZnO is widely used for photodegradation due to its unique physical and chemical properties and stability. In this study, Ag was loaded onto ZnO, which is non-toxic and inexpensive, can improve the electron–hole separation, and has a significant catalytic potential. Pristine ZnO and ZnO-Ag nanoparticles were fabricated by an ultrasonic spray pyrolysis system at different Ag contents (1, 5, and 10 wt%). The carrier gas ratio (O2:N2) was also changed (1:0, 1:2, 1:1, 2:1, and 0:1) to examine its effects on the nanoparticle characteristics. The nanoparticle characteristics were examined using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Brunauer, Emmett, and Teller (BET) specific surface area. The results were interpreted in relation to photodegradation under UV light irradiation. An increase in the ZnO-Ag activity compared with pristine ZnO was observed at a carrier gas ratio of 0:1 with reaction rate constants of 0.0059 and 0.0025 min−1, respectively.

Structured Semiconductors in Photocatalysis

“…The best catalyst with an optimal ratio TiO 2 /Fe = 2 exhibited a high efficiency in the degradation and mineralization of chlordimeform insecticide. Under the optimum conditions, a real effluent loaded with 30 mg L −1 of the insecticide was efficiently treated, leading to 80.8 ± 1.9% TOC reduction after 6 h of treatment, with total removal of the pollutant after only 1 h. Hudandini et al [6] loaded Ag onto ZnO by an ultrasonic spray pyrolysis system at different Ag contents (1, 5, and 10 wt%). An increase in the ZnO-Ag activity compared with pristine ZnO was observed at a carrier gas ratio of 0:1 with reaction rate constants of 0.0059 and 0.0025 min −1 , respectively, in the degradation of textile wastewater under UV light irradiation.…”

Effect of Gas Flowrate on the Properties and Photocatalytic Activity of ZnO-Ag Nanocomposite Materials Prepared by Flame Pyrolysis

“…To the best of our knowledge, the effect of the flowrate on the flame process on the formation of ZnO-Ag composite materials has not been explored. It is known that the characteristics of nanocomposite fabrication are not only caused by the precursor concentration [15], the type of carrier gas [15] as in our recent paper which is to investigate the influence of the characteristics of the photocatalyst produced by using different types of carrier gases (N2 and O2) [16], pyrolysis temperature [12], but also the flow rate of the carrier gas. Therefore, the objective of this study to investigate the effect of the carrier gas flow rate on the ZnO-Ag particle structure in the photocatalytic perfomance as well as the recycling test.…”

Photocatalytic Self-Cleaning PVDF Membrane Blended with MWCNT-ZnO Nanocomposites for RhB Removal

“…Thus, in addition to hydrophilicity, the membranes will also have self-cleaning capacity due to semiconductor oxide which is generally photoactive. Between semiconductor oxides, ZnO is quite popular in the field of photocatalysis due to its non-toxicity and low prices [19]. The photocatalytic process consists in the generation of ROS capable to degrade organic compound by photocatalyst, in this case, ZnO.…”