Nitahara Satoshi, Akiyama Tsuyoshi, Inoue Shinobu, Yamada Sunao
Department of Materials Physics and Chemistry, Graduate School of Engineering, Kyushu University, Hakozaki, Fukuoka 812-8581, Japan.
J Phys Chem B. 2005 Mar 10;109(9):3944-8. doi: 10.1021/jp046776u.
A cathodic-anodic biway photoelectronic device has been successfully constructed using a self-assembled monolayer (SAM). The SAM consists of two kinds of photofunctional thiol derivatives, a ruthenium complex-viologen linked compound (RuVS) and a phthalocyanine derivative (PcS), on a gold electrode. Structural characterization of the SAM has been carried out by absorption spectroscopy, cyclic voltammetry, and differential pulse voltammetry. Photocurrent responses were measured in the presence of methyl viologen (MV2+) and oxygen as electron acceptors and triethanolamine (TEOA) as a sacrificial reagent. For the SAM of RuVS alone, intramolecular electron transfer (ET) was superior to intermolecular ET, resulting in anodic photocurrents even in the presence of MV2+ and oxygen at 0 V vs Ag/AgCl. On the contrary, only cathodic photocurrents were observed at 0 V for the SAM of PcS alone. Photocurrents from the mixed SAM of RuVS and PcS were roughly the sum of individual photocurrents from RuVS and PcS. In fact, photocurrents from the mixed SAM of RuVS and PcS were observed in the anodic direction below approximately 550 nm, and in the cathodic direction above approximately 550 nm at 0 V vs Ag/AgCl. In the case of the mixed SAM of RuS (ruthenium complex disulfide) and PcS, only cathodic photocurrents were observed at 0 V vs Ag/AgCl, due to the lack of an intramolecular ET pathway. The results indicate that in the mixed SAM of RuVS and PcS both dyes can individually function for opposite photocurrent generation. We have also applied the mixed SAM as a photoelectronic logic device by using two LEDs (470 and 640 nm). The system clearly operated as an XOR logic device.
一种阴极 - 阳极双路光电器件已成功利用自组装单分子层（SAM）构建而成。该自组装单分子层由两种光功能硫醇衍生物组成，即在金电极上的钌络合物 - 紫精连接化合物（RuVS）和酞菁衍生物（PcS）。通过吸收光谱、循环伏安法和差分脉冲伏安法对自组装单分子层进行了结构表征。在以甲基紫精（MV2 +）和氧气作为电子受体以及三乙醇胺（TEOA）作为牺牲试剂的情况下测量光电流响应。对于仅含RuVS的自组装单分子层，分子内电子转移（ET）优于分子间电子转移，即使在相对于Ag/AgCl为0 V时存在MV2 +和氧气的情况下也会产生阳极光电流。相反，对于仅含PcS的自组装单分子层，在0 V时仅观察到阴极光电流。来自RuVS和PcS混合自组装单分子层的光电流大致是来自RuVS和PcS的各自光电流之和。实际上，在相对于Ag/AgCl为0 V时，来自RuVS和PcS混合自组装单分子层的光电流在约550 nm以下的阳极方向被观察到，而在约550 nm以上的阴极方向被观察到。在RuS（钌络合物二硫化物）和PcS混合自组装单分子层的情况下，由于缺乏分子内电子转移途径，在相对于Ag/AgCl为0 V时仅观察到阴极光电流。结果表明，在RuVS和PcS的混合自组装单分子层中，两种染料都可以单独发挥作用以产生相反的光电流。我们还通过使用两个发光二极管（470和640 nm）将混合自组装单分子层应用为光电子逻辑器件。该系统明显作为异或逻辑器件运行。
