取代联噻吩染料敏化剂的合成与光伏性能研究

The synthesis and study on the photovoltaic performance of novel substituted bithiophene dye-sensitizers

摘要:

合成了以三苯胺为电子给体，氰基乙酸为电子受体，乙烯基单噻吩、乙烯基联噻吩以及乙烯基烷基取代联噻吩作为共轭桥链的四个有机染料，其分别为TD1、TD2、TD3和TD4。用核磁共振仪、质谱仪和傅立叶变换红外光谱仪对其结构进行了表征。将其运用于染料敏化太阳能电池中，研究了延长共轭桥链、引入烷基链及烷基链的长短对染料光物理、电化学和光伏等性能的影响。结果表明，引入烷基链可以显著地提高短路电流和开路电压，并获得了较高的光电转化效率。其中TD3以己基取代的联噻吩作为π共轭桥链，表现出最大的光电转化效率6.78%，达到了相同条件下测得的N719（7.64%）光电转化效率的88.7%。

Abstract:

Four organic dyes (TD1, TD2, TD3 and TD4) were synthesized which contained triphenylamine (TPA) moieties as electron donors and cyanoacrylic acid moieties as electron acceptors, ethenyl thiophene or ethenyl bithiophene/ alkyl bithiophene as π-conjugated linker. The structures of the molecules were characterized by IR, NMR and MS. The effects of the length of the π-conjugated unit and the alkyl chain on the photo-physical, electrochemical and photovoltaic properties. The results indicated that both short-circuit photocurrent density and open-circuit photovoltage have been remarkably improved by the alkyl-substituent, by which high PCE was obtained. TD3 dye with hexyl-substituted bithiophene as π-conjugated unit, exhibited a satisfied efficiency of 6.78%, which reached ～88.7% of an N719-based DSSCs (7.64%) fabricated and measured under the same conditions.