State Key Laboratory of Fine Chemicals, DUT-KTH Joint Education and Research Centre on Molecular Devices, Dalian University of Technology (DUT), 116012 Dalian, PR China.
ChemSusChem. 2012 May;5(5):913-9. doi: 10.1002/cssc.201100490. Epub 2012 Mar 8.
Noble-metal-free systems with bio-inspired diiron dithiolate mimics of the [FeFe]-hydrogenase active site, namely, [(μ-pdt)Fe(2) (CO)(5) L] [pdt=propanedithiolate; L=P(CH(2) OH)(3) (1), P(CH(3) )(3) (2)], as water reduction catalysts with xanthene dyes as photosensitizers and triethylamine as a sacrificial electron donor were studied for visible-light-driven water reduction to hydrogen. These systems display good catalytic activities with the efficiencies in hydrogen evolution of up to 226 turnovers for 1, if Eosin Y was used as the photosensitizer in an environmentally benign solvent (EtOH/H(2) O) after 15 h of irradiation (λ>450 nm) under optimal conditions. Under all of the conditions adopted, 1 that has a water soluble phosphine ligand, P(CH(2) OH)(3) displayed a higher efficiency than 2, which bears a PMe(3) ligand. The photoinduced electron transfer in the systems was studied using fluorescence, transient absorption, time-resolved UV/Vis, and in situ electron paramagnetic resonance (EPR) spectroscopy. A new electron-transfer mechanism is proposed for hydrogen evolution by these iron-based photocatalytic systems.
具有生物模拟 [FeFe]-氢化酶活性位点的二铁二硫代物模拟物的无贵金属体系，即 [(μ-pdt)Fe(2) (CO)(5) L] [pdt=丙二硫醇；L=P(CH(2) OH)(3) (1)，P(CH(3) )(3) (2)]，作为水还原催化剂，以吖啶染料作为光敏剂，三乙胺作为牺牲电子供体，研究了可见光驱动的水还原为氢气。这些体系在使用 Eosin Y 作为光敏剂的情况下，在环境友好的溶剂 (EtOH/H(2) O) 中，在最佳条件下照射 15 小时后 (λ>450nm)，具有高达 226 次循环的良好催化活性，可用于氢气的产生。在所有采用的条件下，具有水溶性膦配体 P(CH(2) OH)(3) 的 1 比具有 PMe(3) 配体的 2 具有更高的效率。使用荧光、瞬态吸收、时间分辨 UV/Vis 和原位电子顺磁共振 (EPR) 光谱研究了体系中的光致电子转移。提出了这些基于铁的光催化体系进行氢还原的新电子转移机制。
