Abstract: Two novel organic dyes with double D-π-A branches were designed and synthesized as sensitizers for dye sensitized solar cells(DSSCs). These dyes were characterized by mass spectrometry(MS), proton nuclear magnetic resonance spectrometry(1H NMR), and carbon nuclear magnetic resonance spectrometry(13C NMR). The photophysical and electrochemical properties of these two dyes were studied. Relatively high light to electricity conversion efficiency(η) of 4.10% was achieved using dye DP2 as a sensitizer(open-circuit photovoltage Voc=0.63 V, short-circuit photocurrent density Jsc=8.59×10-3A/cm2 and fill factor FF=0.76) under 100×10-3 W/cm2(AM 1.5G). An efficiency of 3.38% for DSSCs based on dye DP1 was observed under the same conditions.

Key words: organic dyes, double D&, ndash, &, pi, &, ndash, A branches, dye-sensitized solar cell, light to electricity conversion efficiency