Synthesis and photoluminescence of metal coated ZnO nanoparticles

ZnO nanoparticles were prepared by precipitation method from zinc nitrate and ammonium carbonate solutions, and annealing at 500°C. The XRD pattern shows that the ZnO nanoparticles have pure wurtzite structure. ZnO nanoparticles were coated with Au, Ag and Pd atoms using wet chemical treatment. The effect of coating ZnO nanoparticles with Au, Ag and Pd atoms on the photoluminescence properties is investigated. Results show that ZnO-plasmonics can play an important role in emission enhancement. In particular, it was found that coating ZnO nanoparticles with metals enhances the ZnO band edge emission by about 11 to 20 %, depending on the type of metal, and quenches the visible emission by about 50 %.