Site-Selective Deposition of Reductive and Oxidative Dual Cocatalysts To Improve the Photocatalytic Hydrogen Production Activity of CaIn2S4 with a Surface Nanostep Structure

Jianjun Ding; Xiangyang Li; Lin Chen; Xian Zhang; Hao Yin; Xingyou Tian

doi:10.1021/acsami.8b17663

Site-Selective Deposition of Reductive and Oxidative Dual Cocatalysts To Improve the Photocatalytic Hydrogen Production Activity of CaIn₂S₄ with a Surface Nanostep Structure

ACS Appl Mater Interfaces. 2019 Jan 9;11(1):835-845. doi: 10.1021/acsami.8b17663. Epub 2018 Dec 28.

Authors

Jianjun Ding^{1

2}, Xiangyang Li^{1

2}, Lin Chen^{1

2}, Xian Zhang^{1

2}, Hao Yin, Xingyou Tian^{1

2}

Affiliations

¹ Institute of Applied Technology, Hefei Institutes of Physical Science , Chinese Academy of Sciences , Hefei 230088 , People's Republic of China.
² CAS Key Laboratory of Photovoltaic and Energy Conservation Materials , Chinese Academy of Sciences , Hefei 230031 , People's Republic of China.

PMID: 30560651
DOI: 10.1021/acsami.8b17663

Abstract

Photocatalytic hydrogen production from water exhibits great potential for solar energy conversion. In this work, using monoclinic CaIn₂S₄ with a surface nanostep structure as a model photocatalyst, we demonstrate a facile and efficient strategy for the construction of AO _x/AuCu/CaIn₂S₄ (A = Mn, Ni, and Pb) composites by site-selective photodeposition of the reductive cocatalyst AuCu alloy and oxidative cocatalyst AO _x on the edge and groove sites of CaIn₂S₄ nanosteps, respectively. Compared to single-cocatalyst composites (AuCu/CaIn₂S₄ and AO _x/CaIn₂S₄) and CaIn₂S₄, the simultaneous deposition of AuCu and AO _x spatially separate the photogenerated charges and the photocatalytic reaction sites, therefore effectively improving the separation efficiency of charge carriers. Meanwhile, the synergistic effect of AuCu and AO _x dual cocatalysts notably reduces the apparent activation energy for the photocatalytic hydrogen production reaction. These novel dual-cocatalyst composites show enhanced performance for hydrogen production under visible light irradiation. A high rate of hydrogen production of 95.75 mmol h^-1 g^-1 is achieved over the MnO _x/AuCu/CaIn₂S₄ composite with the deposition of 0.5 wt % AuCu and 0.2 wt % MnO _x. Our work sheds new lights on designing efficient photocatalytic materials with site-selective surface deposition of reductive and oxidative dual cocatalysts for solar energy conversion.

Keywords: CaIn2S4; activation energy; dual cocatalyst; photocatalytic hydrogen production; spatial separation.