Effect of ZnO seed layer annealing temperature on the growth of ZnO nanorods and its catalytic application

This paper reports the effect of ZnO seed layer annealing temperature on the growth of ZnO nanorods. ZnO nanorods were grown on fluorine-tin oxide (FTO) substrate via simple and facile liquid phase deposition (LPD) at low temperature. High density homogeneous ZnO nanorods have successfully been synthesized directly on the substrate at 60 °C for 4 h reaction time. It was observed that average diameter and length of ZnO nanorod increased, when the annealing temperature increased from 300 °C to 500 °C. Field emission scanning electron microscope (FESEM) images reveal that by increasing the annealing temperature, the homogeneity, particle size, orientation and morphological shape of ZnO nanostructure have been modified. The photoluminescence (PL) spectra reveal the decrease in green emission as the annealing temperature was increased. The UV–Visible characterization confirms the decrease in the transmittance as the annealing temperature was increased. [Display omitted] •The effect of ZnO seed layer annealing temperature on the growth of ZnO nanorods has been studied.•High density homogeneous ZnO nanorods have successfully been synthesized via liquid phase deposition technique.•It was observed that the size of ZnO nanorod increased when the annealing temperature increased from 300 °C to 500 °C.•The best photocatalytic performance corresponds with the annealing temperature of 400 °C.