One pot synthesis of Ag-Au/ZnO nanocomposites: a multi-junction component for sunlight photocatalysis

Abstract

Plasmonic nanoparticles nanoparticles incorporation increases the photo-physical conversion rate in the semiconductors. Here, we demonstrate the one-pot ZnO/(Ag-Au) nanocomposite for enhanced the visible light photocatalysis. The obtained ZnO nanoparticles are of 10-20 nm size and the deposited metal nanoparticles are of 1-3 nm. The light absorbance spectrum indicated the characteristic band edge absorbance of ZnO (similar to 350 nm) as well as the SPR peaks of Ag (similar to 420 nm) and Au (similar to 520 nm). Enhanced absorption received for the metal nanoparticles deposited ZnO nanocrystals indicate the technological importance of the materials. Emission spectrum of the materials indicated the metal nanoparticles inhibited electron-hole pair recombination process. The photocatalytic methylene blue degradation efficiency of ZnO/(Ag-Au) (87%) nanocomposite is much higher than the ZnO/Ag (65%) and ZnO/Au (57%) nanocomposites. Studies indicated the performance improvement is due to the bimetallic nature over their pristine nature of Ag and Au.