A straightforward competent strategy to attune the solid-state morphology, opto-electronic and photovoltaic properties of conjugated co-polymers has been studied by inserting different percentages of N,N-dimethylthiophene-3-carboxamide (TDM) monomeric units. The TDM percentage was varied from 20 to 100%, resulting in widening of the energy band gap. Fabrication of solar cells was performed with ITIC-4F as an electron acceptor to accomplish power conversion efficiencies (PCEs) of 7.8% for P4 (minimum TDM) and 0.85% for P1 (maximum TDM) under a thermal tempering process. A drastic drop in the PCE was noted with increasing percentage of TDM which agrees well with the optical, electronic, and morphological studies. Morphological analysis revealed high crystallinity for P4:ITIC-4F blend having minimum percentage of TDM units compared to its counterparts of higher TDM percentages. A sharp increase in π-π stacking is seen with reduced percentage of TDM units, leading to d spacing of ̴ 3.6 Å. Detailed investigations regarding the charge carrier transport in relation to the π-π stacking of the polymeric film are well implemented in this work.

通过插入不同百分比的 N,N-二甲基噻吩-3-甲酰胺 (TDM) 单体单元，研究了一种直接有效的策略来调整共轭共聚物的固态形态、光电和光伏特性。TDM 百分比从 20% 到 100% 不等，导致能带隙加宽。太阳能电池的制造使用 ITIC-4F 作为电子受体进行，以在热回火工艺下实现 P4（最小 TDM）7.8% 和 P1（最大 TDM）0.85% 的功率转换效率（PCE）。随着 TDM 百分比的增加，PCE 急剧下降，这与光学、电子和形态学研究一致。形态学分析显示 P4 具有高结晶度：与 TDM 百分比较高的同类产品相比，ITIC-4F 混合物的 TDM 单元百分比最低。随着 TDM 单元百分比的降低，π-π 堆叠急剧增加，导致 d 间距为 ̴ 3.6 Å。在这项工作中，对与聚合物薄膜的 π-π 堆叠相关的电荷载流子传输的详细研究得到了很好的实施。