Morphological evolution of Fe doped sea urchin-shaped ZnO nanoparticles with enhanced photocatalytic activity

Abstract

Fe doped sea urchin-shaped ZnO nanoparticles (NPs) were fabricated by the combination of precipitation method and calcination process. X-ray diffraction (XRD), transmission electron microscopy (TEM), field emission scanning electron microscopy (FE-SEM), Brunauer-Emmett-Teller analysis (BET), X-ray photoelectron spectroscopy (XPS) and energy dispersive spectroscopy (EDS) were used to analyze the crystalline structure, morphology, specific surface area, element valence state and elements composition of the obtained samples, respectively. Photocatalytic activity of Fe doped sea urchin-shaped ZnO NPs with different [Fe]/[Zn] molar ratios was monitored in terms of degradation rate and total organic carbon (TOC) removal efficiency by rhodamine B (RhB) degradation under UV light irradiation. Their results indicated that with increased levels of doping content, there was a change in crystallite shape. In addition, increasing levels of the iron content up to 5% results in increased absorption in the visible region of the spectrum, a slightly decreased optical band gap (Eg) and increased photocatalytic activity. It is demonstrated that 5% Fe doped ZnO NPs had smaller size, more uniform dispersion, as well as better photocatalytic activity. Besides, TOC measurement results also make the photocatalytic activity more convincing.