Photoinduced Electron Transfer of PAMAM Dendrimer-Zinc(II) Porphyrin Associates at Polarized Liquid|Liquid Interfaces
Photoinduced Electron Transfer of PAMAM Dendrimer-Zinc(II) Porphyrin Associates at Polarized Liquid|Liquid Interfaces
复制标题
PAMAM 树枝状聚合物-锌 (II) 卟啉缔合物在极化液|液界面的光诱导电子转移
DOI：
10.1021/acs.langmuir.5b01165
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发表时间：
2015
期刊：
影响因子：
3.9
通讯作者：
Hisanori Imura
中科院分区：
文献类型：
--
作者：
Hirohisa Nagatani;Hiroki Sakae;Taishi Torikai;Takamasa Sagara;Hisanori Imura
研究了端氨基聚酰胺胺（PAMAM）树枝状大分子与5，10，15，20-四（4-磺酸基苯基）卟啉锌（ZnTPPS 4-）离子缔合物在极化水溶液中的非均相光诱导电子转移反应|1，2-二氯乙烷（DCE）界面。由亲脂性猝灭剂，十甲基二茂铁，在界面区域的ZnTPPS 4-的光还原所产生的正光电流显着增强的离子缔合与PAMAM树枝状大分子。树枝状聚合物-ZnTPPS 4-缔合物的光电流响应依赖于pH条件和树枝状聚合物的生成。一些阳离子添加剂，如聚烯丙基胺和正辛基三甲基铵也被检查作为替代品的PAMAM树枝状聚合物，但光电流增强的幅度是相当小的。树枝状聚合物-ZnTPPS 4-缔合物的高光反应性主要被解释为与树枝状聚合物稳定缔合的光反应性卟啉单元的高界面浓度的结果，所述树枝状聚合物优选地吸附在极化水上|VCE接口。在第二代和第四代PAMAM树枝状大分子系统中观察到的光化学数据表明，更高代的树枝状大分子，可以将卟啉分子更完全地在内部是效率较低的光电流增强在界面处。这些结果表明，离子反应物在极化液体中的光反应性|液体界面可以通过与带电树枝状聚合物的离子缔合而容易地改性。
The heterogeneous photoinduced electron-transfer reaction of the ion associates between NH2-terminated polyamidoamine (PAMAM) dendrimers and 5,10,15,20-tetrakis(4-sulfonatophenyl)porphyrinato zinc(II) (ZnTPPS4–) was studied at the polarized water|1,2-dichloroethane (DCE) interface. The positive photocurrent arising from the photoreduction of ZnTPPS4–by a lipophilic quencher, decamethylferrocene, in the interfacial region was significantly enhanced by the ion association with the PAMAM dendrimers. The photocurrent response of the dendrimer–ZnTPPS4–associates was dependent on the pH condition and on the generation of dendrimer. A few cationic additives such as polyallylamine andn-octyltrimethyammonium were also examined as alternatives to the PAMAM dendrimer, but the magnitude of the photocurrent enhancement was rather small. The high photoreactivity of the dendrimer–ZnTPPS4–associates was interpreted mainly as a result of the high interfacial concentration of photoreactive porphyrin units associated stably with the dendrimer which was preferably adsorbed at the polarized water|DCE interface. The photochemical data observed in the second and fourth generation PAMAM dendrimer systems demonstrated that the higher generation dendrimer which can incorporate a porphyrin molecule more completely in the interior is less efficient for the photocurrent enhancement at the interface. These results indicated that the photoreactivity of ionic reactant at a polarized liquid|liquid interface can readily be modified via ion association with the charged dendrimer.