Johansson Olof, Borgström Magnus, Lomoth Reiner, Palmblad Magnus, Bergquist Jonas, Hammarström Leif, Sun Licheng, Akermark Björn
Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, 106 91 Stockholm, Sweden.
Inorg Chem. 2003 May 5;42(9):2908-18. doi: 10.1021/ic020420k.
Two series of photosensitizer-electron acceptor complexes have been synthesized and fully characterized: ruthenium(II) tris(bipyridine) ([Ru(II)(bpy)(2)(bpy-X-NDI)], where X = -CH(2)-, tolylene, or phenylene, bpy is 2,2'-bipyridine, and NDI is naphthalenediimide) and ruthenium(II) bis(terpyridine) ([Ru(II)(Y-tpy)(tpy-X-NDI)], where Y = H or tolyl and X = tolylene or phenylene, and tpy = 2,2':6',2' '-terpyridine). The complexes have been studied by cyclic and differential pulse voltammetry and by steady state and time-resolved absorption and emission techniques. Rates for forward and backward electron transfer have been investigated, following photoexcitation of the ruthenium(II) polypyridine moiety. The terpyridine complexes were only marginally affected by the linked diimide unit, and no electron transfer was observed. In the bipyridine complexes we achieved efficient charge separation. For the complexes containing a phenyl link between the ruthenium(II) and diimide moieties, our results suggest a biphasic forward electron-transfer reaction, in which 20% of the charge-separated state was formed via population of the naphthalenediimide triplet state.
已合成并全面表征了两类光敏剂-电子受体配合物：三（联吡啶）钌（II）（[Ru（II）（bpy）₂（bpy-X-NDI）]，其中X = -CH₂-、亚甲苯基或亚苯基，bpy为2,2'-联吡啶，NDI为萘二亚胺）和双（三联吡啶）钌（II）（[Ru（II）（Y-tpy）（tpy-X-NDI）]，其中Y = H或甲苯基且X = 亚甲苯基或亚苯基，tpy = 2,2':6',2''-三联吡啶）。通过循环伏安法和差分脉冲伏安法以及稳态和时间分辨吸收与发射技术对这些配合物进行了研究。在钌（II）多吡啶部分光激发后，对正向和反向电子转移速率进行了研究。三联吡啶配合物仅受到连接的二亚胺单元的轻微影响，未观察到电子转移。在联吡啶配合物中，我们实现了有效的电荷分离。对于在钌（II）和二亚胺部分之间含有苯基连接的配合物，我们的结果表明存在双相正向电子转移反应，其中20%的电荷分离态是通过萘二亚胺三重态的填充形成的。
