Decavoli Cristina, Boldrini Chiara L, Trifiletti Vanira, Luong Sally, Fenwick Oliver, Manfredi Norberto, Abbotto Alessandro
Department of Materials Science, INSTM Unit, Solar Energy Research Center MIB-SOLAR, University of Milano - Bicocca Via R. Cozzi 55 I-20125 Milano Italy
School of Engineering and Materials Science (SEMS), Queen Mary University of London Mile End Road London E1 4NS UK.
RSC Adv. 2021 Jan 28;11(10):5311-5319. doi: 10.1039/d0ra10971a.
Dye-Sensitized Photoelectrochemical Cells (DS-PECs) have been emerging as promising devices for efficient solar-induced water splitting. In DS-PECs, dyes and catalysts for water oxidation and/or reduction are typically two separate components, thus limiting charge transfer efficiency. A small number of organometallic dyes have been integrated with a catalyst to form an integrated dye-catalyst dyad for photoanodes, but until now no dyads based on metal-free organic dyes have been reported for photoanodes. We herein report the first example of dyad-sensitized photoanodes in DS-PEC water splitting based on metal-free organic dyes and a Ru catalyst. The di-branched donor-π-acceptor dyes carry a donor carbazole moiety which has been functionalized with two different terminal pyridyl ligands in order to coordinate a benchmark Ru complex as a water oxidation catalyst, affording water oxidation dyads. The two dyads have been fully characterized in their optical and electrochemical properties, and XPS has been used to confirm the presence of the catalyst bonded to the dye anchored to the semiconductor anode. The two dyads have been investigated in DS-PEC, showing an excellent faradaic efficiency (88% average across all cells, with a best cell efficiency of 95%), thus triggering new perspectives for the design of efficient molecular dyads based on metal-free dyes for DS-PEC water splitting.
染料敏化光电化学电池（DS-PECs）已成为用于高效太阳能诱导水分解的有前景的装置。在DS-PECs中，用于水氧化和/或还原的染料和催化剂通常是两个单独的组件，从而限制了电荷转移效率。少数有机金属染料已与催化剂整合形成用于光阳极的集成染料-催化剂二元体系，但迄今为止，尚未有基于无金属有机染料的二元体系用于光阳极的报道。我们在此报告了基于无金属有机染料和钌催化剂的DS-PEC水分解中二元体系敏化光阳极的首个实例。二分支供体-π-受体染料带有供体咔唑部分，该部分已用两种不同的末端吡啶基配体进行功能化，以便配位一种基准钌配合物作为水氧化催化剂，从而得到水氧化二元体系。这两种二元体系的光学和电化学性质已得到充分表征，并且X射线光电子能谱（XPS）已用于确认与锚定在半导体阳极上的染料结合的催化剂的存在。这两种二元体系已在DS-PEC中进行了研究，显示出优异的法拉第效率（所有电池的平均效率为88%，最佳电池效率为95%），从而为基于无金属染料设计用于DS-PEC水分解的高效分子二元体系开启了新的前景。
