Two novel high gap donor polymers – PBDTTSi-TzBI and PBDTTS-TzBI, based on imide fused benzotriazole (TzBI) with asymmetric side chains and alkylsilyl (Si) or alkylthio (S) substituted 4,8-di (thien-2-yl)benzo [1,2-b:4,5-b′]dithiophene (BDTT) – are successfully synthesized. The effect of the side chain variation on the photophysical, morphological and photovoltaic properties of blends of these polymers with fullerene and non-fullerene acceptors is investigated. The PBDTTSi-TzBI polymer shows a deeper highest occupied molecular orbital energy level, which results in higher open-circuit voltages. Nevertheless, the polymer solar cells fabricated using PBDTTS-TzBI in combination with PC₇₁BM afford a higher power conversion efficiency of 7.3% (vs 4.0% for PBDTTSi-TzBI:PC₇₁BM). By using the non-fullerene acceptor ITIC, the absorption of the blends extends to 850 nm and better device efficiencies are achieved, 6.9% and 9.6% for PBDTTSi-TzBI:ITIC and BDTTS-TzBI:ITIC, respectively. The better performance for PBDTTS-TzBI:ITIC is attributed to the strong and broad absorption and balanced charge transport, and is among the best so far for non-fullerene solar cells based on TzBI-containing polymer donors.

两种新型的高间隙供体聚合物-PBDTTSi-TzBI和PBDTTS-TzBI，基于具有不对称侧链的酰亚胺稠合苯并三唑（TzBI）和烷基甲硅烷基（Si）或烷硫基（S）取代的4,8-二（噻吩-2-基）苯并[1,2- b：4,5- b ']二噻吩（BDTT）–已成功合成。研究了侧链变化对这些聚合物与富勒烯和非富勒烯受体共混物的光物理，形态和光伏性质的影响。所述PBDTTSi-TzBI聚合物显示更深的最高占据分子轨道能级的能量水平，这导致更高的开路电压。尽管如此，使用PBDTTS-TzBI与PC结合制造的聚合物太阳能电池₇₁ BM的功率转换效率更高，为7.3％（PBDTTSi-TzBI：PC ₇₁ BM的功率转换效率为4.0％）。通过使用非富勒烯受体ITIC，共混物的吸收扩展到850 nm，并实现了更高的器件效率，PBDTTSi-TzBI：ITIC和BDTTS-TzBI：ITIC分别为6.9％和9.6％。PBDTTS-TzBI：ITIC的更好性能归因于其强大而广泛的吸收和平衡的电荷传输，并且是迄今为止基于含TzBI的聚合物供体的非富勒烯太阳能电池的最佳性能之一。