开发了一类新型阳极界面缓冲材料PbI_2,制备了结构为ITO/PbI_2/P3HT:PC_(61)BM/Al(氧化铟锡导电玻璃/碘化铅/聚三已基噻吩:富勒烯衍生物/铝)的器件,制备工艺包括旋涂和蒸镀,考察了PbI_2在聚合物太阳能电池原型器件ITO/P3HT:PC_(61)BM/Al中的效果。不同碘化铅浓度,退火温度,退火时间,对PbI_2薄膜的质量都会有影响。很显然,高质量的PbI_2薄膜将会带来好的光电转化效率。PbI_2薄膜的透光性,结晶性,以及表面形貌可以用来描述所成薄膜的质量好坏。对能带来最好性能的碘化铅薄膜进行了紫外-可见光谱,X射线粉末衍射(XRD),原子力显微镜(AFM),扫描电子显微镜(SEM)等表征。实验发现,太阳能电池器件的效率对PbI_2浓度比较敏感,最优化的条件为,旋涂浓度为3 mg?m L^(-1),100°C退火30 min,其电池的开路电压(Voc)达到0.45 V,短路电流密度(Jsc)为7.9 m A?cm^(-2),填充因子(FF)为0.46,与没有界面缓冲材料的器件相比,光电转换效率(PCE)由0.85%提高到1.64%。
We develop a novel hole extracting buffer layer material,namely PbI_2.The structure of the device we fabricate is ITO/PbI_2/P3HT:PC_(61)BM/Al(indium tin oxide/lead iodide/poly(3-hexylthiophene):[6,6]-phenyl C61-butyric acid methyl ester/aluminum cathode).The preparation method involves spin-coating and thermal evaporation.We study the effectiveness of using PbI_2 in the prototype ITO/P3HT:PC_(61)BM/Al polymer solar cell devices.The concentration,annealing temperature,and annealing time all have an influence on the quality of the PbI_2 films.Obviously,higher-quality PbI_2 films will lead to better power conversion efficiency.The transmittance,crystallization,and morphology properties of the PbI_2 films can be used to describe the quality of the films.We characterize the PbI_2 film affording the best performance by UV-Vis spectrophotometry,X-ray powder diffraction(XRD),atomic force microscopy(AFM),and scanning electron microscopy(SEM).Our results reveal that the performance of the solar cell device is sensitive to the concentration of PbI_2,and the best conditions are a concentration of 3 mg?m L~(-1),annealing temperature of 100 °C,and annealing time of 30 min.The open circuit voltage(Voc) is 0.45 V,the short circuit current density(Jsc) is 7.9 m A?cm~(-2),and the fill factor(FF) is 0.46.Compared with the devices without any buffer layer(0.85%),the power conversion efficiency(PCE)using PbI_2 as the buffer layer can reach 1.64%.