Controlled microwave-assisted and pH-affected growth of ZnO structures and their photocatalytic performance

A fast microwave-assisted method was used to grow zinc oxide. The synthesis was carried out under three different pH conditions (8, 10 and 12) with the precipitation agent triethylamine. The obtained materials were comprehensively characterised using X-ray diffraction (XRD), scanning and transmission electron microscopy (SEM and TEM), low-temperature N-2 sorption (BET model), and analysis of electrokinetic potential and thermal stability (TGA). It was established that the pH value had a significant impact on the crystallinity, morphology and thermal stability of the final products. The primary purpose of this study was to use the synthesised materials in a process of photodegradation (in the UV light range) of the model organic pollutant - 4-chlorophenol (20 mg/dm(3)). The photo-oxidation tests showed that the obtained zinc oxide materials exhibit good photodegradation and mineralisation efficiency. Moreover, the kinetics of the photocatalytic degradation of 4-chlorophenol were determined based on the pseudo-first-order model, assuming the LangmuirHinshelwood mechanism. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

A fast microwave-assisted method was used to grow zinc oxide under different pH conditions, resulting in materials with varying crystallinity, morphology, and thermal stability. The obtained zinc oxide materials showed good photodegradation and mineralisation efficiency of the model organic pollutant, 4-chlorophenol, in the UV light range. The kinetics of the photocatalytic degradation of 4-chlorophenol were determined based on a pseudo-first-order model, assuming the Langmuir-Hinshelwood mechanism.