著者
Hirohisa NAGATANI Satoshi DEJIMA Hiroki HOTTA Toru OZEKI Toshiyuki OSAKAI
出版者
The Japan Society for Analytical Chemistry
雑誌
Analytical Sciences (ISSN:09106340)
巻号頁・発行日
vol.20, no.11, pp.1575-1579, 2004 (Released:2005-03-03)
参考文献数
31
被引用文献数
5 8 2

The photocurrent at the polarized water/1,2-dichloroethane (DCE) interface was successfully observed in the presence of a lipophilic sensitizer, 5,10,15,20-tetraphenylporphyrinato zinc (ZnTPP), in the organic phase. The photocurrent transient responses were apparently affected by the employed organic supporting electrolyte: tetrapenthylammonium tetraphenylborate (TPnATPB) or tris(tetraoctylammonium)tungstophosphate ((TOcA)3PW12O40). The photocurrent measured in the TPnATPB system exhibited rather slow responses associated with the ion transfer of photoproducts. On the other hand, the photoinduced heterogeneous electron transfer could be observed in the use of (TOcA)3PW12O40. The photocurrent intensity in the (TOcA)3PW12O40 system exhibited an apparent pH dependence and the photoreduction of hydrogen ions probably took place at the water/DCE interface. By analyzing the real and imaginary components of the photocurrent depending on the photoexcitation frequency, we roughly estimated the phenomenological rate constants of the product separation (kps) and recombination (krec) processes as log(kps/s-1) = 1.5 ± 0.2 and log(krec/s-1) = 1.8 ± 0.1, respectively.