敏化染料分子长径比对太阳能电池性能的影响

Effect of Aspect Ratio of the Dye Molecule on the Properties of Dye Sensitized Solar Cells

采用同一系列但分子长径比不同的3种染料:2-氰基-3-[2-[4-{2-[4-N,N-二(4-甲基苯基)氨基苯基]乙烯基}-苯基氨基)-嘧啶-5-取代基]-丙烯酸(MTPA-Pyc)、2-氰基-3-(4-{2-[4-N,N-二(4-甲基苯基)氨基苯基]乙烯基}-苯基)-丙烯酸(MTPAcc)和2-氰基-3-[4-N,N-二(4-甲基苯基)氨基苯基]-丙烯酸(MTPAc),研究了在不同吸附溶剂中3种染料分子在Ti O2上的吸附量和聚集态,探讨了敏化染料分子长径比对染料敏化太阳电池性能的影响.结果表明,MTPAcc具有最合适的分子长径比,其在Ti O2表面的吸附量及应用的光电性能最高;吸附溶剂的极性增大有利于提高染料的吸附量,但也会影响染料分子的聚集态.当以四氢呋喃为吸附溶剂时,MTPAcc在Ti O2表面的吸附量大且不发生聚集,对应的敏化太阳能电池器件在所有结果中表现最好,在490 nm处的单色光光电转化效率(IPCE)极值达到84%,总光电转化效率(η)达到5.72%.

Three dyes,2-cyano-3-[2-（ 4-{ 2-[4-N,N-bis（ 4-methylphenyl） aminophenyl]vinyl}-phenylamino）-pyrimidin-5-yl]-acrylic acid（ MTPA-Pyc）,2-cyano-3-（ 4-{ 2-[4-N,N-bis（ 4-methylphenyl） aminophenyl]vinyl }-phenyl）-acrylic acid（ MTPAcc）,and 2-cyano-3-[4-N,N-bis（ 4-methylphenyl） aminophenyl]-acrylic acid（ MTPAc）,that have different aspect ratios were studied for their performances as sensitizer in a dye sensitized solar cell（ DSSC）. The effects of solvent,the amount of dye molecules adsorbed on the surface of Ti O2,and dye aggregation were investigated. The results show that MTPAcc has the most suitable aspect ratio among the three dyes with the highest and best photovoltaic properties. Polariry of absorption solvents can influence not only the absorbed amount of dyes at Ti O2 but also the dye aggregation. MTPA-Pyc with a large aspect ratio exists in H-aggregation in tolene and tetrahydrofuran,whereas J-aggregation in acetonitrile.MTPAcc was found with high absorption amount at Ti O2 but without aggregation,resulting in the best photovoltaic properties of corresponding DSSC with the incident photon-to-current efficiency（ IPCE） of 84% at 490 nm and the photoelectric conversion efficiency（ η） of 5. 72%. Therefore,the aspect ratio of dye sensitizers is significant for the photovoltaic properties of DSSC.