Abstract Three novel polymers with D-A (π)-BT backbone, PBDBT-0, PBDBT-1, and PBDBT-2, were built through effective side-chain chlorination strategies and thiophene-induced approaches. Meanwhile, the effect of different thiophene numbers was studied. As expected, all of the chlorinated polymers showed low HOMO levels. The introduction of the thiophene unit improved the solubility of the polymer and slightly adjusted the energy level of the molecule. Furthermore, polymers as donors and PC71BM as acceptors are used to construct organic solar cell devices. The devices based on polymer PBDBT-1 with one thiophene unit delivered the best efficiency of 5.73 % with an open-circuit voltage of 0.85 V, a short-circuit current density of 13.07 mA cm−2 and a fill factor of 51.6 %, which is superior to that of PBDBT-0 and PBDBT-2.

中文翻译：

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用于调节高性能有机聚合物太阳能电池分子能级的氯化和噻吩策略

摘要 通过有效的侧链氯化策略和噻吩诱导方法构建了三种具有 DA (π)-BT 主链的新型聚合物 PBDBT-0、PBDBT-1 和 PBDBT-2。同时，研究了不同噻吩数量的影响。正如预期的那样，所有氯化聚合物都显示出低 HOMO 水平。噻吩单元的引入提高了聚合物的溶解度，并略微调整了分子的能级。此外，聚合物作为供体和 PC71BM 作为受体用于构建有机太阳能电池器件。基于聚合物 PBDBT-1 和一个噻吩单元的器件在 0.85 V 的开路电压、13.07 mA cm-2 的短路电流密度和 51.6 % 的填充因子下提供了 5.73% 的最佳效率，其中优于 PBDBT-0 和 PBDBT-2。