One Step Synthesis and Characterization of ZnO–ZnSe Heterostructures by Chemical Precipitation and Its Solar Photocatalytic Activity

Abstract

ZnO–ZnSe heterostructures were successfully synthesized by single step chemical precipitation method at room temperature. The obtained composite structures were systematically characterized for structural, morphological, optical, and vibrational properties using X-ray diffraction (XRD), field emission scanning electron microscope (FESEM), High-resolution transmission electron microscopy (HRTEM), UV–Vis DRS, photoluminescence spectroscopy (PL), and Fourier-transform Raman spectroscopy (FT-Raman). XRD patterns of the synthesized samples exhibit peaks corresponding to wurtzite ZnO and ZnSe structures which primarily confirmed the formation of single phase heterostructures. ZnO microspheres grown over the surface of ZnSe nano cauliflower clusters obtained from the FESEM images confirmed the formation of ZnO–ZnSe heterostructures. A sharp peak around 290 nm in UV–Vis DRS absorption spectra corresponds to ZnSeO3 and a wide weak absorbance is observed in the visible region (ranging from 370 to 663 nm) corresponding to the nanocomposite structure. In the Raman spectra, the surface phonon mode which is the characteristic feature of the ZnO–ZnSe heterostructures is observed at 237 cm−1. Based on the characterization results, the photocatalytic properties of ZnO–ZnSe nanoparticles were evaluated for the degradation of methylene blue (MB) and was found to exhibit solar photocatalytic property.