作者:N. A. Davidenko、N. A. Derevyanko、A. A. Ishchenko、N. G. Kuvshinsky、A. V. Kulinich、O. Ya. Neiland、M. V. Plotniece
DOI:10.1007/s11172-005-0016-y
日期:2004.8
Polymer composition films based on polystyrene and containing electron donors, viz., substituted tetrathiafulvalenes, an electron acceptor, viz., 2,4,5,7-tetranitrofluoren-9-one, and sensitizers, viz., a cationic polymethine dye, 1,3,3-trimethyl-2-[3-(1,3-dihydro-1,3,3-trimethyl-2H-indol-2-ylidene)prop-1-en-1-yl]-3H-indolium tetrafluoroborate, and a neutral merocyanine dye, 5-3-[(1,3-dihydro-1,3,3-trimethyl-2H-indol-2-ylidene)ethylidene]-2-phenyl-cyclopent-1-en-1-ylmethylene}-2-thioxodihydropyrimidine-4,6(1H,5H)-dione, were prepared. The internal photo effect upon film irradiation in the near-IR range is provided by low ionization potentials of the donors and the high electron affinity of the acceptor. The photoconductivity increases upon replacement of a cationic dye by a neutral one, mainly because of photogeneration of mobile charge carriers of both signs and a decrease in the activation energy for the photoconduction current. The decrease in the activation energy for the photocurrent is due to the fact that in the case of a neutral dye, the mobile charge carriers move away from each other during their separation, while in the case of a cationic dye, the colorless counterion strongly holds the photo generated charge carrier.
基于聚苯乙烯并含有电子供体(即取代的四噻吩戊烯)、电子受体(即 2,4,5,7-四硝基芴-9-酮)和敏化剂(即 1,3,3-三甲基-2-[3-(1,3-二氢-1,3,3-三甲基-2H-吲哚-2-亚基)丙基]的聚合物组成薄膜、阳离子聚甲基染料、1,3,3-三甲基-2-[3-(1,3-二氢-1,3,3-三甲基-2H-吲哚-2-亚基)丙-1-烯-1-基]-3H-吲哚鎓四氟硼酸盐和中性美蓝染料、制备了 5-3-[(1,3-二氢-1,3,3-三甲基-2H-吲哚-2-亚基)乙亚基]-2-苯基-环戊-1-烯-1-基亚甲基}-2-硫酮二氢嘧啶-4,6(1H,5H)-二酮。供体的低电离电位和受体的高电子亲和力使薄膜在近红外范围内照射时产生内部光效应。用中性染料取代阳离子染料后,光导率会增加,这主要是由于两种符号的移动电荷载流子的光生成以及光导电流活化能的降低。光电流活化能降低的原因是,在中性染料的情况下,移动电荷载流子在分离过程中会相互远离,而在阳离子染料的情况下,无色反离子会牢牢抓住光生电荷载流子。