高结晶度方酸菁染料全溶液制备平面异质结有机太阳能电池

All Solution-Processed Planar Heterojunction Organic Solar Cells Using A Highly Crystalline Squaraine Dye

高结晶度有机半导体材料由于分子紧密堆叠,电荷迁移率高,但其在普通有机溶剂中溶解度低,溶液可加工性较差,限制了其在有机光电产品中的应用。本文设计合成了一种甲基修饰的高结晶度方酸菁类染料(DM-SQ),利用三氟乙酸溶剂溶液涂布制备DM-SQ薄膜。研究发现溶液制备的DM-SQ薄膜结晶度高,与真空沉积的DM-SQ薄膜比较,空穴迁移率更高(5.28×10^-4 vs.7.53×10^-5 cm^2·V^-1·s^-1)。以DM-SQ作为给体,PC61BM作为受体,制备了平面异质结太阳能电池。溶液法制备的器件平均能量转换效率明显高于真空沉积器件(6.08±0.19%和3.56±0.22%)。

Highly crystalline organic semiconductors with close molecular stacking could hold high charge mobility but low solubility in common organic solvents,limiting their solution processability for organic optoelectronics.Herein,a methyl-decorated high-crystalline squaraine dye(DM-SQ)is synthesized,and a highly crystalline thin film is solution-deposited using trifluoroacetic acid(TFA)as solvent.The resultant film shows a higher hole mobility as compared with that of the vacuum-deposited film(5.28×10^-4 vs.7.53×10^-5 cm^2·V^-1·s^-1).With DM-SQ as donor and PC61 BM(phenyl-C61-butyric acid methyl ester)as acceptor,the solution-processed planar heterojunction solar cells exhibit an average power conversion efficiency of 6.08±0.19%,higher than 3.56±0.22%for the vacuum-deposited devices.