The Research Of Advanced Organic Polymer Solar Cells In Preparation Technology

Recent progress in the development of polymer solar cells has improved power-conversion efficiencies from3%to almost9%. Based on semiconducting polymers, these solar cells are fabricated from solution-processing techniques and have unique prospects for achieving low-cost solar energy harvesting, owing to their material and manufacturing advantages. The potential applications of polymer solar cells are broad, ranging from flexible solar modules and semitransparent solar cells, to building applications. In this thesis, we aimed at preparation technology of organic solar cells based on polymer, and mainly explored in three aspects:The ternary blend films have been fabricated via adding4,4’-N,N’-dicarbazole-biphenyl (CBP, a hole transport material widely used in organic light emitting diodes) into the poly(3-hexylthiophene):[6,6]-phenyl C61-butyric acid methyl ester (P3HT:PC61BM). The solar cell utilizing the optimized P3HT:PC61BM:CBP blend film showed the increases of16.1%in power conversion efficiency (PCE) and25.1%in short-circuit current than the one using the reference P3HT:PC61BM blend film.The influence of introducing a small amount of NPB into the mixed P3HT:PC61BM solution on the performance of the polymer solar cells was investigated. It was found that adding NPB improved bulk heterojunction grown which enhanced the photovoltaic performance. When NPB content is0.4mg/mL, PCE increased from1.05%to1.64%.We studied the ternary blend films composed of low-degree of polymerization poly [2,6-(4,4-bi s-(2-ethylhexyl)-4H-cyclopenta[2,1-b;3,4-b’] dithiophene)-alt-4,7-(2,1,3-be nzothiadiazole)](LDP-PCPDTBT), PC61BM and polymethylmethacrylate (PMMA), processed with and without1,8-dibromooctane as solvent additive. The LDP-PCPDTBT and PC61BM phases in the PMMA matrix were characterized amorphous and crystalline, respectively, without the additive processing, while both the crystallinity of the LDP-PCPDTBT component and the aggregation of PC61BM component could be significantly promoted with the additive processing. The power conversion efficiency of solar cell was increased50%by the additive processing, as a result of the increased open-circuit voltage and the optimized phase separation of LDP-PCPDTBT and PC61BM in the PMMA matrix.