title: In situ growth of matchlike ZnO/Au plasmonic heterostructure for enhanced photoelectrochemical water splitting.
abstract: In this paper, we report a novel matchlike zinc oxide (ZnO)/gold (Au) heterostructure with plasmonic-enhanced photoelectrochemical (PEC) activity for solar hydrogen production. The matchlike heterostructure with Au nanoparticles coated on the tip of ZnO nanorods is in situ grown on a zinc (Zn) substrate by using a facile hydrothermal and photoreduction combined approach. This unique heterostructure exhibits plasmonic-enhanced light absorption, efficient charge separation and transportation properties with tunable Au contents. The photocurrent density of the matchlike ZnO/Au heterostructure reaches 9.11 mA/cm(2) at an applied potential of 1.0 V (vs Ag/AgCl) with an Au/Zn atomic ratio of 0.039, which is much higher than that of the pristine ZnO nanorod array (0.33 mA/cm(2)). Moreover, the solar-to-hydrogen conversion efficiency of this special heterostructure can reach 0.48%, 16 times higher than that of the pristine ZnO nanorod array (0.03%). What is more, the efficiency could be further improved by optimizing the Au content of the heterostructure. The formation mechanism of such a unique heterostructure is proposed to explain the plasmonic-enhanced PEC performance. This study might contribute to the rational design of the visible-light-responsive plasmonic semiconductor/metal heterostructure photoanode to harvest the solar spectrum.
authors.affiliation: Innovation Lab for Clean Energy and Green Catalysis, School of Chemistry and Chemical Engineering, Anhui University , Hefei 230601, P. R. China.
authors.forename: Mi
authors.initials: M
authors.lastname: Wu
authors.forename: Wei-Jian
authors.initials: WJ
authors.lastname: Chen
authors.forename: Yu-Hua
authors.initials: YH
authors.lastname: Shen
authors.forename: Fang-Zhi
authors.initials: FZ
authors.lastname: Huang
authors.forename: Chuan-Hao
authors.initials: CH
authors.lastname: Li
authors.forename: Shi-Kuo
authors.initials: SK
authors.lastname: Li
keywords: PEC water splitting; matchlike ZnO/Au heterostructure; photoanode; photoreduction; surface plasmon resonance