Levin Natalia, Casadevall Carla, Cutsail George E, Lloret-Fillol Julio, DeBeer Serena, Rüdiger Olaf
Max Planck Institute for Chemical Energy Conversion Stiftstr. 34-36 D-45470 Mülheim an der Ruhr Germany.
Institute of Chemical Research of Catalonia (ICIQ) Avinguda Països Catalans, 16 43007 Tarragona Spain.
ChemElectroChem. 2022 Feb 11;9(3):e202101271. doi: 10.1002/celc.202101271. Epub 2021 Dec 27.
In this study, we combine in situ spectroelectrochemistry coupled with electron paramagnetic resonance (EPR) and X-ray absorption spectroscopies (XAS) to investigate a molecular Ru-based water oxidation catalyst bearing a polypyridinic backbone . Although high valent key intermediate species arising in catalytic cycles of this family of compounds have remain elusive due to the lack of additional anionic ligands that could potentially stabilize them, mechanistic studies performed on this system proposed a water nucleophilic attack (WNA) mechanism for the O-O bond formation. Employing experimental conditions and complementary spectroscopic techniques allowed to observe intermediates that provide support for a WNA mechanism, including for the first time a Ru(V) oxo intermediate based on the ligand, in agreement with the previously proposed mechanism.
在本研究中，我们将原位光谱电化学与电子顺磁共振（EPR）和X射线吸收光谱（XAS）相结合，以研究一种具有聚吡啶主链的分子钌基水氧化催化剂。尽管由于缺乏可能稳定它们的额外阴离子配体，这类化合物催化循环中产生的高价关键中间物种仍然难以捉摸，但对该系统进行的机理研究提出了一种用于O-O键形成的水亲核攻击（WNA）机制。采用实验条件和互补光谱技术能够观察到为WNA机制提供支持的中间体，包括首次基于该配体观察到的Ru(V)氧代中间体，这与先前提出的机制一致。
