本研究设计合成了一种分子内梯度能级、含二元π共轭单元的有机染料C217。此染料以3,4-乙烯二氧基噻吩(EDOT)与二并噻吩的顺序偶联结构作为染料的共轭系统,结合三芳胺给体和氰基乙酸受体,实现了染料的宽光谱吸收。该染料在以乙腈为电解质溶剂的器件中达到了9.8%的光电转换效率;结合无溶剂离子液体电解质,实现了光电转换效率达8.1%的长期光热稳定的染料敏化太阳电池,其性能已经非常接近钌染料。这一研究成果将促进宽光谱、高效率、低成本有机染料敏化太阳电池的开发和应用。
We have synthesized a high molar extinction coefficient organic sensitizer with a binary π-conjugated spacer exhibiting an almost panchromatic photocurrent response.In conjunction with a volatile acetonitrile electrolyte and a solvent-free ionic liquid electrolyte,unprecedented high efficiencies of 9.8% and 8.1% measured under AM1.5G full sunlight have been reached for organic dye-sensitized solar cells.For the first time,we have demonstrated a stable,8% efficiency,solvent-free dye-sensitized solar cell based on metal-free organic sensitizers.This achievement will considerably encourage further molecular and energy-level engineering of low-cost metal-free organic dyes,boosting the practical application of dye-sensitized solar cells.