Synthesis and characterization of sodium doped ZnO nanocrystals and its application to photocatalysis

Abstract Pure and Na-doped ZnO photocatalysts (Na–ZnO) were synthesized by simple wet chemical method using zinc acetate dehydrate as starting material and samples were annealed at 350 °C. The results of characterization techniques like XRD, SEM, EDXA and UV reveals that the prepared samples were nanometer in size and Na ions successfully doped into the ZnO lattice without change its wurtzite structure. The effect of addition of different concentration of sodium dopant on structural property, optical property, surface morphology and photo-catalytic activity of ZnO nanocrystals were analyzed. By using methylene blue as a model dye the photo-catalytic decolourisation was studied and the results shows that the sodium doped ZnO proves higher photo-catalytic decolourisation than the pure ZnO. This increase is possible as a result of sodium doping in the crystal structure of ZnO. A possible mechanism of the photocatalytic decolourisation of methylene blue on the sodium doped ZnO is suggested.