Investigating outstanding properties of phosphorus containing ZnO microparticles synthesized through hydrothermal process

Zinc oxide is attracted great attention as it indicates a high photocatalytic efficiency similar to or greater than titanium dioxide, good biocompatibility and environmental stability [۱]. ZnO can replace TiO۲ because of its physical and chemical properties and also its bandgap which is similar to that of the TiO۲. The ultraviolet wavelengths should be used due to the large bandgap of the ZnO [۲]. However, the charge carriers’ recombination in ZnO is relatively high which restricts its extensive application in the photocatalytic reactions. To tackle this challenge, diverse methods have been adopted. Non-metal and metal doping is an effective method for reducing band gap and improving charge carriers’ separation and changing the wavelength threshold of absobed light to the visible area [۳]. In this research, a phosphorus containing ZnO photocatalyst containing ۱.۸ wt.% of phosphorus (ZnO-P۱.۸%) was successfully synthesized using the hydrothermal method. The structural, physical and optical properties of the obtained microparticles were investigated using varied methods including scanning electron microscopy (SEM) image, X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, ultraviolet-visible diffusion reflectance spectroscopy (UV-Vis DRS), and photoluminescence (PL) spectroscopy. The SEM image illustrated that the ZnO-P۱.۸% had a rod-like morphology so that some rods were joint together to form a flower-like shape but some of the rods were isolated and exhibited regular hexagonal and/or conical shapes. The PL spectrum showed six peaks in the range of ۴۰۰ to ۶۰۰ nm including a broad peak near ۴۲۰ nm, three sharp peaks at around ۴۴۵, ۴۶۰ and ۴۸۰ nm along with two broad peaks at about ۵۳۰ and ۵۷۵ nm.