Oshima Takayoshi, Nishioka Shunta, Kikuchi Yuka, Hirai Shota, Yanagisawa Kei-Ichi, Eguchi Miharu, Miseki Yugo, Yokoi Toshiyuki, Yui Tatsuto, Kimoto Koji, Sayama Kazuhiro, Ishitani Osamu, Mallouk Thomas E, Maeda Kazuhiko
Department of Chemistry, School of Science, Tokyo Institute of Technology, 2-12-1-NE-2 Ookayama, Meguro-ku, Tokyo 152-8550, Japan.
Japan Society for the Promotion of Science, Kojimachi Business Centre Building, 5-3-1 Kojimachi, Chiyoda-ku, Tokyo 102-0083, Japan.
J Am Chem Soc. 2020 May 6;142(18):8412-8420. doi: 10.1021/jacs.0c02053. Epub 2020 Apr 27.
Sensitization of a wide-gap oxide semiconductor with a visible-light-absorbing dye has been studied for decades as a means of producing H 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 H and O using HCaNbO nanosheets sensitized by a Ru(II) tris-diimine type photosensitizer, in combination with a WO-based water oxidation photocatalyst and a triiodide/iodide redox couple. With the use of Pt-intercalated HCaNbO nanosheets further modified with amorphous AlO clusters as the H evolution component, the dye-based turnover number and frequency for H evolution reached 4580 and 1960 h, 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 H production, and represents a significant leap forward in the development of solar-driven water splitting systems.
几十年来，人们一直在研究用吸收可见光的染料对宽禁带氧化物半导体进行敏化，以此作为从水中制取氢气的一种方法。然而，使用染料敏化氧化物光催化剂实现高效的全分解水仍然是一个尚未解决的挑战。在此，我们展示了利用钌（II）三双亚胺型光敏剂敏化的铌酸钙氢纳米片，结合基于氧化钨的水氧化光催化剂和三碘化物/碘化物氧化还原对，实现可见光驱动的全分解水生成氢气和氧气。使用经非晶态氧化铝簇进一步修饰的铂插层铌酸钙氢纳米片作为析氢组分，基于染料的析氢周转数和频率分别达到了4580和1960 h⁻¹。使用420 nm光进行全分解水的表观量子产率为2.4%，这是迄今为止报道的染料敏化全分解水体系中最高的。目前的工作清楚地表明，精心设计的染料/氧化物杂化物在光催化制氢方面具有巨大潜力，代表了太阳能驱动水分解系统发展的一个重大飞跃。
