Sasaki Yoshiko, Araki Yasuyuki, Ito Osamu, Alam Maksudul M
Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Katahira, Sendai 980-8577, Japan.
Photochem Photobiol Sci. 2007 May;6(5):560-5. doi: 10.1039/b617229f. Epub 2007 Jan 31.
Photoinduced electron transfer processes between fullerenes (C60) and four phenothiazine derivatives (PTZs) in the absence and presence of hexylviologen dication (HV2+) have been studied by the transient absorption method in the visible and near-IR regions. Electron-transfer takes place from PTZs to the triplet states of fullerenes (3C60*) giving the radical anion of fullerenes (C60.-) and the radical cations of PTZs (PTZ.+). The rate constants and efficiencies of electron transfer are quite high, because of the high electron-donor abilities of PTZs as elucidated by their low oxidation potentials. On addition of HV2+ to the C60 and PTZ systems, the electron-mediating process occurs from C60.- to HV2+, yielding the viologen radical cation (HV.+). In the presence of a sacrificial donor, HV.+ persisted for a long time.
通过可见和近红外区域的瞬态吸收方法，研究了在不存在和存在己基紫精二价阳离子（HV2+）的情况下，富勒烯（C60）与四种吩噻嗪衍生物（PTZs）之间的光诱导电子转移过程。电子从PTZs转移到富勒烯的三重态（3C60*），生成富勒烯的自由基阴离子（C60.-）和PTZs的自由基阳离子（PTZ.+）。由于PTZs具有高电子供体能力，这由它们的低氧化电位所阐明，因此电子转移的速率常数和效率相当高。向C60和PTZ体系中加入HV2+后，电子介导过程从C60.-发生到HV2+，产生紫精自由基阳离子（HV.+）。在存在牺牲供体的情况下，HV.+能长时间持续存在。
