title: Preparation of a squaraine-bounded cellulose derivative for photocurrent generation system.
abstract: A regio-selectively squaraine (SQ)-bounded cellulose derivative (4) with a degree of substitution of SQ (DSSQ) of 0.55 was prepared from 6-O-(4-methoxytrityl) cellulose (1) by three reaction steps in 77% total yield. Lauryl SQ carboxylate (8) was also prepared as a reference sample. The photostability of SQ moieties of compound 4 in CHCl3 was not improved when compared with SQ-COOH (7), but that of SQ moiety of compound 8 was improved unexpectedly. The Langmuir-Blodgett monolayer films 4B and 8B on an indium tin oxide (ITO) electrode were successfully prepared from compounds 4 and 8 by a vertical dipping method, respectively. The films 4B and 8B showed photocurrent generation performances in the region of 550-680 nm. The quantum yield at 650 nm of film 4B was higher than that of film 8B. These results showed that the cellulose backbone of compound 4 acts as an effective scaffold for the good photocurrent generation performances and that compound 4 was a promising complementary material of the porphyrin-bounded cellulose derivatives (for photocurrent generation at 400-420 nm) for effective utilization of solar light, as well as the phthalocyanine-bounded cellulose derivatives (for photocurrent generation at 650-720 nm).
authors.affiliation: Division of Forest and Biomaterials Science, Graduate School of Agriculture, Kyoto University, Kyoto, Japan.
authors.forename: Yasuko
authors.initials: Y
authors.lastname: Saito
authors.affiliation: Division of Forest and Biomaterials Science, Graduate School of Agriculture, Kyoto University, Kyoto, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kamitakahara
authors.affiliation: Division of Forest and Biomaterials Science, Graduate School of Agriculture, Kyoto University, Kyoto, Japan. Electronic address: takatmys@kais.kyoto-u.ac.jp.
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Takano
mesh_terms: D002482:Cellulose / Q000737:chemistry*; D003503:Cyclobutanes / Q000138:chemical synthesis* / Q000737:chemistry; D015394:Molecular Structure; D010636:Phenols / Q000138:chemical synthesis* / Q000737:chemistry; D010777:Photochemistry; D011789:Quantum Theory
chemical_list: D003503:Cyclobutanes; D010636:Phenols; C480596:squaraine; D002482:Cellulose
keywords: Cellulose; LB film; Photosensitizer; Squaraine