以3,4-乙撑二氧噻吩(EDOT)为电子给体单元、烷基链取代的四苯基环戊二烯酮分子为电子受体单元,采用Stille偶联法合成了一种新型的低能带隙交替共聚物(DPPD)。利用核磁共振(NMR)、紫外-可见光谱(UV-Vis)、凝胶渗透色谱(GPC)、循环伏安(CV)、热重分析(TGA)、示差量热分析(DSC)等对共聚物进行了表征。结果表明:共聚物具有良好的溶解性和热稳定性,热分解温度为376.6℃,数均分子量为1.45×104,分子量分布为1.13,光学能带隙约为1.55 eV,500~750 nm有较宽的吸收。以共聚物DPPD和富勒烯C60衍生物[6,6]-苯基-C61丁酸甲酯(PC60BM)制备的本体异质结器件开路电压为0.63 V,短路电流为0.45 mA/cm2,填充因子为0.28,能量转换效率为0.08%。
A novel low band gap alternating copolymer,with 3,4-ethylenedioxythiophene(EDOT) as an electron donor and alkyl chains substituted tetraphenyl cyclopentadienone as an electron acceptor,was successfully synthesized via Stille crosscoupling polymerization.The new conjugated polymer was characte-(rized) by NMR,UV-Vis,GPC,CV,TGA and DSC.Results show that the macromolecule has good solubility and thermal stability with thermal decomposition temperature at 376.6 ℃.The number average(molecular) weight(M_n) is 1.45×10~4 with polydispersity of 1.13.UV-Vis spectroscopy indicates a low band gap(about 1.55 eV) of the copolymer and a broad absorption from 500 nm to 750 nm.A bulk heterojunction device with the new copolymer and -phenyl-C_(61) butyric acid methyl ester(PC_(60)BM) as the(activity) layer was fabricated.It shows an open circuit voltage of 0.63 V,a short circuit current of 0.45 mA/cm~2,the fill factor of 0.28 and the power conversion efficiency of 0.08%.