主链含噻唑单元的新型聚噻吩衍生物的合成与光伏性能

Synthesis and Photovoltaic Properties of Novel Polythiophene Derivative Containing Thiazoles in Main Chain

聚噻吩(PT)衍生物由于简单易合成和较好的光电性能,被广泛运用于有机太阳能电池(OSCs)中,但PT较高的能级限制了其在非富勒烯类OSCs的应用。为了降低PT的能级结构,本研究将噻唑单元引入到聚噻吩主链中,设计并合成了新型聚合物给体材料PBTzCl-T。通过紫外-可见吸收光谱、电化学循环伏安法及密度泛函理论(DFT)计算等对聚合物的结构、光学和电学性能进行了表征,并对制备的光伏器件进行了光电性质研究。结果表明:噻唑的引入能够有效降低聚合物的HOMO和LUMO能级,从而提高光伏器件的开路电压。PBTzCl-T在不同溶剂中表现出不同的预聚集行为,进而影响聚合物给受体界面处的电荷转移能力和活性层形貌,导致光伏器件的短路电流和填充因子变化。

Polythiophene(PT)derivatives are widely used in organic solar cells due to their simple synthesis and good photoelectric properties,but their development is limited by their high energy level.Therefore,in order to reduce its energy level structure,this paper introduced thiazole into the polythiophene derivative backbone chain to synthesize a new polymer donor PBTzCl-T.The photoelectric properties were studied by UV-Vis absorption spectroscopy,electrochemical cyclic voltammetry and density functional theory(DFT)calculation.The results show that the introduction of thiazoles can effectively reduce the HOMO and LUMO levels of polymers,thus improving the open circuit voltage of photovoltaic devices.Meanwhile,PBTzCl-T exhibits different preaggregation behaviors in different solvents,which affects the charge transfer ability and active layer morphology of polymer at the interface of D/A,leading to the change of short-circuit current and filling factor of photovoltaic devices.