PEG functionalized ZnO nanoparticles by fusion of precipitation-cum-hydrothermal method with enhanced photocatalytic activity

In this study, polyethylene glycol (PEG)-aided zinc oxide (ZnO) nanoparticles (NPs) have been synthesized by fusion of precipitation-cum-hydrothermal method. The PEG/ZnO NPs were investigated by x-ray diffraction (XRD), Fourier-transform infrared (FTIR) transformation, UV-visible field emission scanning electron microscope (FESEM), energy dispersive x-ray, high resolution transmission electron microscope (HRTEM), and RAMAN techniques. XRD analysis confirms the formation of the wurtzite phase with a crystallite size of 8 nm of synthesized PEG/ZnO. While FESEM and HRTEM investigations reveal the formation of distinct structural forms, FTIR investigations show interactions between PEG and ZnO. High crystallinity of PEG/ZnO is observed in the selected area electron diffraction pattern. The Brunauer–Emmett–Teller (BET) study revealed that ZnO NPs have a mesoporous structure with a significant specific surface area of 42 m2 g−1. The evaluation of photocatalytic activity of PEG/ZnO-based photocatalyst was carried out via the degradation of typical azo dye (industrial methylene blue (MB) dye) along with total organic carbon (TOC) analysis. The PEG-ZnO (dose 200 mg l−1) was found to be an efficient photocatalyst for the degradation of MB dye. The degradation reaction exhibits pseudo-first-order kinetics. Additionally, TOC removal was monitored, elucidating almost complete mineralization.