An Artificial Z-Scheme Constructed from Dye-Sensitized Metal Oxide Nanosheets for Visible Light-Driven Overall Water Splitting

Takayoshi Oshima; Shunta Nishioka; Yuka Kikuchi; Shota Hirai; Kei-Ichi Yanagisawa; Miharu Eguchi; Yugo Miseki; Toshiyuki Yokoi; Tatsuto Yui; Koji Kimoto; Kazuhiro Sayama; Osamu Ishitani; Thomas E Mallouk; Kazuhiko Maeda

doi:10.1021/jacs.0c02053

An Artificial Z-Scheme Constructed from Dye-Sensitized Metal Oxide Nanosheets for Visible Light-Driven Overall Water Splitting

J Am Chem Soc. 2020 May 6;142(18):8412-8420. doi: 10.1021/jacs.0c02053. Epub 2020 Apr 27.

Authors

Takayoshi Oshima^{1

2}, Shunta Nishioka^{1

2

3}, Yuka Kikuchi⁴, Shota Hirai¹, Kei-Ichi Yanagisawa⁵, Miharu Eguchi⁶, Yugo Miseki⁷, Toshiyuki Yokoi⁸, Tatsuto Yui⁴, Koji Kimoto⁵, Kazuhiro Sayama⁷, Osamu Ishitani¹, Thomas E Mallouk^{3

9}, Kazuhiko Maeda¹

Affiliations

¹ Department of Chemistry, School of Science, Tokyo Institute of Technology, 2-12-1-NE-2 Ookayama, Meguro-ku, Tokyo 152-8550, Japan.
² Japan Society for the Promotion of Science, Kojimachi Business Centre Building, 5-3-1 Kojimachi, Chiyoda-ku, Tokyo 102-0083, Japan.
³ Department of Chemistry, University of Pennsylvania, 231 S. 34th Street, Philadelphia, Pennsylvania 19104, United States.
⁴ Graduate School of Science and Technology, Niigata University, 8050 Ikarashi-2, Niigata 950-2181, Japan.
⁵ Research Center for Advanced Measurement and Characterization, National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan.
⁶ Research Center for Functional Materials, National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan.
⁷ Research Center for Photovoltaics (RCPV) and Global Zero Emission Research Center (GZR), National Institute of Advanced Industrial Science and Technology (AIST), Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565 Japan.
⁸ Nanospace Catalysis Unit, Institute of Innovative Research, Tokyo Institute of Technology, 4259-S2-5, Nagatsuta, Midori-ku, Yokohama 226-8503, Japan.
⁹ International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan.

PMID: 32282192
DOI: 10.1021/jacs.0c02053

Abstract

Sensitization of a wide-gap oxide semiconductor with a visible-light-absorbing dye has been studied for decades as a means of producing H₂ from water. However, efficient overall water splitting using a dye-sensitized oxide photocatalyst has remained an unmet challenge. Here we demonstrate visible-light-driven overall water splitting into H₂ and O₂ using HCa₂Nb₃O₁₀ nanosheets sensitized by a Ru(II) tris-diimine type photosensitizer, in combination with a WO₃-based water oxidation photocatalyst and a triiodide/iodide redox couple. With the use of Pt-intercalated HCa₂Nb₃O₁₀ nanosheets further modified with amorphous Al₂O₃ clusters as the H₂ evolution component, the dye-based turnover number and frequency for H₂ evolution reached 4580 and 1960 h^-1, respectively. The apparent quantum yield for overall water splitting using 420 nm light was 2.4%, by far the highest among dye-sensitized overall water splitting systems reported to date. The present work clearly shows that a carefully designed dye/oxide hybrid has great potential for photocatalytic H₂ production, and represents a significant leap forward in the development of solar-driven water splitting systems.