Fast and Efficient Sun Light Photocatalytic Activity of Au_ZnO Core-Shell Nanoparticles Prepared by a One-Pot Synthesis

Luca Spitaleri; Giuseppe Nicotra; Massimo Zimbone; Annalinda Contino; Giuseppe Maccarrone; Alessandra Alberti; Antonino Gulino

doi:10.1021/acsomega.9b01850

Fast and Efficient Sun Light Photocatalytic Activity of Au_ZnO Core-Shell Nanoparticles Prepared by a One-Pot Synthesis

ACS Omega. 2019 Sep 9;4(12):15061-15066. doi: 10.1021/acsomega.9b01850. eCollection 2019 Sep 17.

Authors

Luca Spitaleri¹, Giuseppe Nicotra², Massimo Zimbone³, Annalinda Contino¹, Giuseppe Maccarrone¹, Alessandra Alberti², Antonino Gulino^{1

4}

Affiliations

¹ Department of Chemical Sciences, University of Catania, Viale Andrea Doria 6, 95125 Catania, Italy.
² CNR-IMM, Zona industriale Strada VIII, 5, 95121 Catania, Italy.
³ CNR-IMM, via S. Sofia 64, 95123 Catania, Italy.
⁴ INSTM UdR of Catania, Viale Andrea Doria 6, 95125 Catania, Italy.

Abstract

Gold nanostructures absorb visible light and show localized surface plasmon resonance bands in the visible region. Semiconducting ZnO nanostructures are excellent for ultraviolet detection, thanks to their wide band gap, large free exciton binding energy, and high electron mobility. Therefore, the coupling of gold and ZnO nanostructures represents the best-suited way to boost photodetection. With the above perspective, we report on the high photocatalytic activity of some Au_ZnO core-shell nanoparticles (NPs) recently prepared by a one-pot synthesis in which a [zinc citrate]^- complex acted as the ZnO precursor, a reducing agent for Au³⁺, and a capping anion for the obtained Au NPs. The overall nanostructures proved to be Au(111) NPs surrounded by a thin layer of [zinc citrate]^- that evolved to Au_ZnO core-shell nanostructures. Worthy of note, with this photocatalyst, sun light efficiently decomposes a standard methylene blue solution according to ISO 10678:2010. We rationalized photodetection, reaction rate, and quantum efficiency.