van 't Hoff Institute for Molecular Sciences, University of Amsterdam, Science Park 904, Amsterdam, 1098 XH, The Netherlands.
Chemistry. 2019 Nov 4;25(61):13921-13929. doi: 10.1002/chem.201902514. Epub 2019 Sep 26.
Artificial photosynthesis-the direct photochemical generation of hydrogen from water-is a promising but scientifically challenging future technology. Because nature employs membranes for photodriven reactions, the aim of this work is to elucidate the effect of membranes on artificial photocatalysis. To do so, a combination of electrochemistry, photocatalysis, and time-resolved spectroscopy on vesicle-embedded [FeFe]hydrogenase mimics, driven by a ruthenium tris-2,2'-bipyridine photosensitizer, is reported. The membrane effects encountered can be summarized as follows: the presence of vesicles steers the reactivity of the [FeFe]-benzodithiolate catalyst towards disproportionation, instead of protonation, due to membrane characteristics, such as providing a constant local effective pH, and concentrating and organizing species inside the membrane. The maximum turnover number is limited by photodegradation of the resting state in the catalytic cycle. Understanding these fundamental productive and destructive pathways in complex photochemical systems allows progress towards the development of efficient artificial leaves.
人工光合作用——直接从水中光化学产生氢气——是一项很有前景但具有科学挑战性的未来技术。由于自然界利用膜进行光驱动反应，因此本工作旨在阐明膜对人工光催化的影响。为此，报道了一种结合电化学、光催化和时间分辨光谱学的方法，用于研究囊泡嵌入的[FeFe]氢化酶模拟物，该模拟物由钌三-2,2'-联吡啶光引发剂驱动。遇到的膜效应可以概括为：囊泡的存在使[FeFe]-苯并二硫醇催化剂的反应性朝着歧化而不是质子化的方向发展，这是由于膜的特性，例如提供恒定的局部有效 pH 值，并在膜内浓缩和组织物种。最大周转率受催化循环中休息状态的光降解限制。理解这些复杂光化学系统中的基本生产和破坏途径，可以促进高效人工叶子的发展。
