Charge Photo-Accumulation and Photocatalytic Hydrogen Evolution Under Visible Light at an Iridium(III)-Photosensitized Polyoxotungstate.
Charge Photo-Accumulation and Photocatalytic Hydrogen Evolution Under Visible Light at an Iridium(III)-Photosensitized Polyoxotungstate.
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DOI：
10.1039/c3ee40352a
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发表时间：
2013-05
影响因子：
32.5
通讯作者：
Proust A
中科院分区：
文献类型：
--
作者：
Matt B;Fize J;Moussa J;Amouri H;Pereira A;Artero V;Izzet G;Proust A
报道了共价 Ir(III) 光敏多钨酸盐在可见光下的稳态照射。在牺牲电子供体存在下，光解导致多金属氧酸盐非常有效的光还原。通过与光谱电化学测量相比，可以明确地识别出一电子和二电子还原物质的连续形成，并且观察到单电子还原物质形成的反应速率明显更快。光还原动力学与多金属氧酸盐 (POM) 的还原电位相关，可以通过酸的存在进行微调。事实上，在乙酸的存在下，光驱动的双电子还原 POM 的形成得到显着促进。该系统还能够在可见光下进行光催化制氢，连续光解超过1周，性能没有明显损失，并且表现出比相关多组分系统更高的光催化效率，概述了POM和光敏剂之间的共价键合的决定性作用。这种功能性和模块化系统为电荷光累积装置和随后的人工光合作用光电催化剂的开发迈出了有希望的一步。
Steady-state irradiation under visible light of a covalent Ir(III)-photosensitized polyoxotungstate is reported. In the presence of a sacrificial electron donor, the photolysis leads to the very efficient photoreduction of the polyoxometalate. Successive formation of the one-electron and two-electron reduced species, which are unambiguously identified by comparison with spectroelectrochemical measurements, is observed with a significantly faster rate reaction for the formation of the one-electron reduced species. The kinetics of the photoreduction, which are correlated to the reduction potentials of the polyoxometalate (POM), can be finely tuned by the presence of an acid. Indeed light-driven formation of the two-electron reduced POM is considerably facilitated in the presence of acetic acid. The system is also able to perform photocatalytic hydrogen production under visible light without significant loss of performance over more than 1 week of continuous photolysis and displays higher photocatalytic efficiency than the related multi-component system, outlining the decisive effect of the covalent bonding between the POM and the photosensitizer. This functional and modular system constitutes a promising step for the development of charge photoaccumulation devices and subsequent photoelectrocatalysts for artificial photosynthesis.