Facile synthesis of ZnO@NiFe-LDH nanocomposites for efficient photocatalytic degradation of methylene blue under natural sunlight irradiation

In this study, wet chemical methods are employed to synthesize zinc oxide nanocomposites in combination with nickel-iron layered double hydroxides (ZnO@NiFe-LDH). A structural analysis confirmed that ZnO@NiFe-LDH nanocomposites possess tunable surface properties and have been successfully formed. The photocatalytic degradation of methylene blue in aqueous solution was demonstrated under the influence of natural sunlight. A number of photocatalytic parameters were observed, including the initial dye concentration, the pH of the dye solution, anionic effects, and cycling stability. During the deposition of ZnO, 0.75 g of NiFe-LDH was added, resulting in ZnO@NiFe-LDH/3 with the lowest optical band gap of 2.68 eV. A degradation efficiency of 99% was observed for ZnO@NiFe-LDH/3. In the repeatable five degradation cycles of the ZnO@NiFe-LDH nanocomposite, the degradation kinetics followed pseudo-first order, with a slight decrease in degradation efficiency from 99 to 88%. In order to validate the effects of real wastewater environments on the degradation performance of the ZnO@NiFe-LDH nanocomposite, a study was conducted with anionic compounds, such as chloride, sulfate, and nitrate. Results showed that anionic compounds such as chloride, sulfate, and nitrate had a negligible effect on degradation. It is evident from the results of this study that the photocatalyst protocol may have great potential for wastewater treatment.