Structural, morphological, optical and photocatalytic properties of Ag-doped ZnO nanoparticles

In this work, pure ZnO and Ag-doped ZnO nanoparticles (NPs) have been synthesized by the simple sol–gel route. The studies on as-synthesized ZnO and Ag-doped ZnO NPs have been conducted using X-ray diffraction (XRD), scanning electron microscopy, transmission electron microscopy (TEM), UV–visible spectroscopy and photocatalytic measurement. The powder XRD pattern indicates that the Ag-doped ZnO samples possess crystalline behavior and exhibits hexagonal wurtzite structure with average crystalline size in the range of 6.58–20.37 nm. TEM measurement confirms the particle size and hexagonal phase of Ag-doped ZnO NPs. The optical properties of the as-prepared nanoparticles were examined using UV–visible and the optical band gap of Ag-doped ZnO NPs is found to be between 2.96 and 3.07 eV that have decreased from bandgap of 3.13 eV of pure ZnO NPs. The near band emissions at around 389, 396, 404 and 410 nm are observed for pure and Ag-doped ZnO NPs in addition to deep level emission at higher wavelength in the visible region. The photocatalytic studies of NPs showed to enhanced degradation of methylene blue with Ag-doped ZnO NPs comparable to ZnO nanoparticles.