通过Stille偶联聚合方法合成一种新型的Pechmann类窄带隙聚合物(PBDTTP),并将其应用到太阳能电池的研究中。PBDTTP具有高的相对分子质量、良好的溶解性能与成膜性能。紫外-可见吸收光谱表明,在薄膜状态下,PBDTTP的吸收范围在300~900 nm 之间,其最大吸收峰位置在748 nm,相应的光学带隙为1.37 eV。光伏器件的结构为(ITO)/PEDOT:PSS/PBDTTP:PC71BM/Al,初步的器件结果显示,当PBDTTP与PC71BM质量比为1:2时,光伏器件具有最高的能量转换效率(PCE),为1.03%,对应的开路电压(Voc)为0.75 V,短路电流密度(Jsc)为2.24 mA/cm2,填充因子(FF)为61.2%。
A new low bandgap Pechmann-based polymer (PBDTTP) was synthesized, and this is the first time to make Pechmann-based polymer for photovoltaic applications. PBDTTP was found to be soluble in common organic solvents, with excellent film forming properties. The gel permeation chromatography (GPC) shows that the polymer has relatively high relative molecular mass. The polymer film exhibits broad absorption band in the wavelength region from 300 to 900 nm with an optical bandgap of 1.37 eV. Preliminary photovoltaic cells based on the composite structure of ITO/PEDOT:PSS/PBDTTP:PC71BM/Al show an open-circuit voltage Voc of 0.75 V, a power conversion efficiency (PCE) of 1.03%, a short circuit current density (Jsc) of 2.24 mA/cm2 and a fill factor of 61.2%.