Photochemical Synthesis of Hierarchical Multiple-Growth-Hillock Superstructures of Silver Nanoparticles on ZnO

Abstract

Hierarchical superstructures of Ag nanoparticles with novel morphology resembling multiple growth hillocks were synthesized for the first time using photochemical method through the screw-dislocation-driven, nanoparticle-mediated crystal growth mechanism. The Ag nanoparticles were in situ synthesized from the photoreduction of Ag+ ions adsorbed on ZnO. The absence of organic capping agents in the synthesis protocol makes this photochemical approach suitable for preparing metal/semiconductor hybrid materials with clean metal/semiconductor interfaces that can find important applications in plasmon-assisted photocatalysis, photovoltaics, and plasmon-enhanced spectroscopies. Finally, we demonstrated that the photoluminescence properties of ZnO can be subtly modified by the photodeposited Ag nanostructures through synergistic mechanisms of surface plasmon–exciton resonant coupling and surface passivation.