A new approach is presented here to maximize the efficiency of ternary blend polymer solar cells (ter-PSCs). The properties of co-absorbing wide band-gap polymers are fine-tuned via the insertion of two different appropriate electron-acceptor units on their backbone in different ratios, and the resulting polymers are utilized as a co-absorbent on ter-PSCs. The copolymerization of benzodithiophene, pyrrolopyrrole-1,3-dione, and difluoro-benzothiadiazole derivatives at three different ratios, 1.00:1.00:0.00, 1.00:0.50:0.50, and 1.00:0.25:0.75, produces the polymers P1–P3. The absorption bands of P1–P3 are gradually red-shifted, and the band-gaps are reduced. The crystallinity of the polymers is increased in the order of P1 < P2 < P3. The binary polymer solar cells (bi-PSCs) are fabricated using blends of P1, P2, or P3 with PC₇₀BM and provide comparable power conversion efficiencies (PCEs) of 5.41%, 5.55%, and 4.01%, respectively. However, the inclusion of 20 wt% of each of P1, P2, and P3 on a P4 (=PTB7-Th):PC₇₀BM blend offers PCEs of 9.31%, 9.60%, and 9.85%, respectively, which are higher than that of the bi-PSC made using a blend of P4:PC₇₀BM (PCE = 8.20%). The improved absorption, crystallinity, and carrier mobilities of the ternary blends are the main reasons for their enhanced photovoltaic performance compared with the binary blends.

此处提出了一种新方法，可最大程度地提高三元共混聚合物太阳能电池（ter-PSC）的效率。通过在主链上以不同比例插入两个不同的合适电子受体单元，可以微调共吸收宽带隙聚合物的性能，并将所得聚合物用作三元PSC的共吸收剂。苯并二噻吩，吡咯并吡咯-1,3-二酮和二氟-苯并噻二唑衍生物以三种不同的比例1.00：1.00：0.00、1.00：0.50：0.50和1.00：0.25：0.75进行共聚，生成聚合物P1-P3。P1-P3的吸收带逐渐红移，带隙减小。聚合物的结晶度按P1  <  P2  < 的顺序增加P3。二元聚合物太阳能电池（bi-PSC）是使用P1，P2或P3与PC ₇₀ BM的混合物制成的，可提供分别为5.41％，5.55％和4.01％的可比功率转换效率（PCE）。但是，在P4（= PTB7-Th）：PC ₇₀ BM共混物中包含P1，P2和P3各自20 wt％的PCE分别为9.31％，9.60％和9.85％，这是更高的比使用P4：PC ₇₀ BM（PCE）的混合物制成的bi-PSC = 8.20％）。与二元共混物相比，三元共混物改善的吸收，结晶度和载流子迁移率是其增强的光伏性能的主要原因。