Department of Chemistry, Bowling Green State University, Bowling Green, Ohio 43403, USA.
Inorg Chem. 2011 Feb 7;50(3):705-7. doi: 10.1021/ic101731j. Epub 2011 Jan 4.
Three platinum(II) terpyridylacetylide charge-transfer complexes possessing a lone ancillary ligand systematically varied in phenylacetylide π-conjugation length, [Pt((t)Bu(3)tpy)(C≡CC(6)H(4)H)]ClO(4) (n = 1-3), are evaluated as photosensitizers (PSs) for visible-light-driven (λ > 420 nm) hydrogen production in the presence of a cobaloxime catalyst and the sacrificial electron donor triethanolamine (TEOA). Excited-state reductive quenching of the PS by TEOA produces PS(-) (k(q) scales with the driving force as 1 > 2 > 3), enabling thermal electron transfer to the cobalt catalyst. The initial H(2) evolution is directly proportional to the incident photon flux and visible-light harvesting capacity of the sensitizer, 3 > 2 > 1. The combined data suggest that PSs exhibiting attenuated bimolecular reductive quenching constants with respect to the diffusion limit can overcome this deficiency through improved light absorption in homogeneous H(2)-evolving compositions.
三种具有孤电子辅助配体的铂（II）三吡啶基乙炔电荷转移配合物，其苯乙炔π-共轭长度系统变化，[Pt((t)Bu(3)tpy)(C≡CC(6)H(4)H)]ClO(4)（n = 1-3），被评估为可见光驱动（λ>420nm）的光催化剂（PSs）在钴卟啉催化剂和牺牲电子供体三乙醇胺（TEOA）存在下进行产氢反应。PS 被 TEOA 的激发态还原猝灭产生 PS(-)（k(q)与驱动力的比例为 1>2>3），从而能够进行热电子转移到钴催化剂。初始 H(2)的产生与入射光子通量和敏化剂的可见光捕获能力直接成正比，3>2>1。综合数据表明，与扩散极限相比，表现出减弱的双分子还原猝灭常数的 PS 可以通过在均相 H(2)产生组成中改善光吸收来克服这一缺陷。
