以 1,3-環己二烯及芴官能基為主體之有機染料研究及其染料敏化太陽能電池應用

Abstract

本文中探討以芴基 (fluorenyl) 為推電子端，羧酸根為拉電子基團，而推拉電子基團中間以不同的共軛片段，如苯環、噻吩 (thiophene) 及1,3-環己二烯，設計成推電子端- 共軛-拉電子端 (Donor- conjugated system-Acceptor (D--A) 形式的染料 dh19、dh123、dh。本文中成功合成出染料 dh19 及 dh123，分別進行了核磁共振結構鑑定、高解析質譜結構鑑定、紫外光-可見光吸收光譜、循環伏特安培法、太陽能電池的光電轉換效率、EIS (electrochemical impedance spectroscopy) 等的實驗。以 AM 1.5 irradiation (100 mW/cm2) 所測得光電轉換效率，以 dh123  = 3.63% 為最高，其中 dh123 的 Jsc = 8.23 mA/cm2 高於 dh19 許多，推測可能原因是 dh123 有較出色的吸收光子能力，不論是消光係數還是紫外光-可見光吸收光譜波長涵蓋範圍，dh123 皆是較優秀的，而且 dh19 及 dh123 在吸附量上差異不大，因此 dh123 擁有較大的電流密度。In this study, a series of dipolar organic dyes (dh19、dh123、dh) composed of a fluorenylamine donor, aromatic  conjugated framework, and 1,3-cyclohexdiene carboxylic acid acceptor have been synthesized. The photophysical and electrochemical properties of these dyes were studied in details. The amount of dye adsorption on TiO2 and the oxidation potential are dependent on the dye structure. The higher performances were obtained by DSSCs based on dye dh123. The solar-to-electrical energy conversion efficiency () of 3.63% is achieved under simulated AM 1.5 irradiation (100 mW/cm2) with a DSSC based on dye dh123 (Voc = 672 mV, Jsc = 8.23 mA/cm2, ff = 0.66). The better cell performance of dh123 over dh19 is attributed to higher extinction coefficient and better light-harvesting in the case of dh123.