Five 4,7-dithien-2-yl-2,1,3-benzothiadiazole （DTBT）-based conjugated copolymers with controlled molecular weight were synthesized to explore their optical, energy level and photovoltaic properties. By tuning the pos...Five 4,7-dithien-2-yl-2,1,3-benzothiadiazole （DTBT）-based conjugated copolymers with controlled molecular weight were synthesized to explore their optical, energy level and photovoltaic properties. By tuning the positions of hexyl side chains on DTBT unit, the DTBT- fluorene copolymers exhibited very different aggregation properties, leading to 60 nm bathochromic shift in their absorptions and the corresponding power conversion efficiencies （PCEs） value of photovoltaic cells varied from 0.38%, 0.69% to 2.47%. Different copolymerization units, fluorene, earbazole and phenothiazine were also investigated. The polymer based on phenothiazine exhib- ited lower PCE value due to much lower molecular weight owing to its poor solubility, although phenothiazine units were expected to be a better electron donor. Compared with the fluorene-based polymer, the carbazole-DTBT copolymer showed higher short circuit current density （Jsc） and PCE value due to its better intermolecular stacking,展开更多
采用Suzuki缩合聚合方法,将4,6-苯并噻二唑单元引入到聚合物中,合成了4,6-苯并噻二唑-咔唑共聚物P1,研究了其光学性质和电化学性质.结果表明,与4,7-位结构类似物(HBC)相比,P1在Mn=12000时仍易溶于甲苯,二氯甲烷等一般的有机溶剂中;其薄...采用Suzuki缩合聚合方法,将4,6-苯并噻二唑单元引入到聚合物中,合成了4,6-苯并噻二唑-咔唑共聚物P1,研究了其光学性质和电化学性质.结果表明,与4,7-位结构类似物(HBC)相比,P1在Mn=12000时仍易溶于甲苯,二氯甲烷等一般的有机溶剂中;其薄膜状态时的紫外吸收光谱和光致发光光谱分别蓝移78和43 nm;光学带宽和电化学带宽分别增大0.35和0.40 e V,而循环伏安曲线的形状不变;说明4,6-位苯并噻二唑单元的引入,有效地改善了苯并噻二唑类聚合物的溶解性能,调节了光电性能,但保留了苯并噻二唑单元优异的电化学稳定性和可逆性.4,6-位苯并噻二唑单元的引入为实现苯并噻二唑类聚合物材料的多性能调节提供了一种新的手段和方法.展开更多
基金Acknowledgements Financial support by the National Natural Science Foundation of China （Grant Nos. 51073063 and 20904057） and Open Project of State Key Laboralory for Supramolecular Structure and Materials （No. SKLSSM201129） of Jilin university arc gratefully acknowledged. J. Zhang thanks the support by 100 Talents Programme of the Chinese Academy of Science.
文摘Five 4,7-dithien-2-yl-2,1,3-benzothiadiazole （DTBT）-based conjugated copolymers with controlled molecular weight were synthesized to explore their optical, energy level and photovoltaic properties. By tuning the positions of hexyl side chains on DTBT unit, the DTBT- fluorene copolymers exhibited very different aggregation properties, leading to 60 nm bathochromic shift in their absorptions and the corresponding power conversion efficiencies （PCEs） value of photovoltaic cells varied from 0.38%, 0.69% to 2.47%. Different copolymerization units, fluorene, earbazole and phenothiazine were also investigated. The polymer based on phenothiazine exhib- ited lower PCE value due to much lower molecular weight owing to its poor solubility, although phenothiazine units were expected to be a better electron donor. Compared with the fluorene-based polymer, the carbazole-DTBT copolymer showed higher short circuit current density （Jsc） and PCE value due to its better intermolecular stacking,
文摘采用Suzuki缩合聚合方法,将4,6-苯并噻二唑单元引入到聚合物中,合成了4,6-苯并噻二唑-咔唑共聚物P1,研究了其光学性质和电化学性质.结果表明,与4,7-位结构类似物(HBC)相比,P1在Mn=12000时仍易溶于甲苯,二氯甲烷等一般的有机溶剂中;其薄膜状态时的紫外吸收光谱和光致发光光谱分别蓝移78和43 nm;光学带宽和电化学带宽分别增大0.35和0.40 e V,而循环伏安曲线的形状不变;说明4,6-位苯并噻二唑单元的引入,有效地改善了苯并噻二唑类聚合物的溶解性能,调节了光电性能,但保留了苯并噻二唑单元优异的电化学稳定性和可逆性.4,6-位苯并噻二唑单元的引入为实现苯并噻二唑类聚合物材料的多性能调节提供了一种新的手段和方法.
