Effects of a benzotriazole (BTA)-based small molecule, BTA2, as the third component on the charge carrier generation and recombination behavior of poly [[4,8-bis[(2-ethylhexyl)oxy]benzo[1,2-b:4,5-b’]dithio-phene-2,6-diyl][3-fluoro-2-[(2-ethylhexyl)carbonyl]thieno [3,4-b]thiophenediyl]] (PTB7): [6,6]-phenyl-C₇₁-butyric acid methyl ester (PC₇₁BM) organic solar cells (OSCs) were investigated by optical simulation of a transfer matrix model (TMM), photo-induced charge extraction by linearly increasing voltage (photo-CELIV) technique, atomic force microscope (AFM), and the Onsager-Braun model analysis. BTA2 is an A₂-A₁-D-A₁-A₂-type non-fullerene small molecule with thiazolidine-2,4-dione, BTA, and indacenodithiophene as the terminal acceptor (A₂), bridge acceptor (A₁), and central donor (D), respectively. The short-circuit current density of the OSCs with BTA2 can be enhanced significantly owing to a complementary absorption spectrum. The optical simulation of TMM shows that the ternary OSCs exhibit higher internal absorption than the traditional binary OSCs without BTA2, resulting in more photogenerated excitons in the ternary OSCs. The photo-CELIV investigation indicates that the ternary OSCs suffer higher charge trap-limited bimolecular recombination than the binary OSCs. AFM images show that BTA2 aggravates the phase separation between the donor and the acceptor, which is disadvantageous to charge carrier transport. The Onsager-Braun model analysis confirms that despite the charge collection efficiency of the ternary OSCs being lower than that of the binary OSCs, the optimized photon absorption and exciton generation processes of the ternary OSCs achieve an increase in photogenerated current and thus improve power conversion efficiency.

基于苯并三唑（BTA）的小分子BTA2作为第三组分对聚[[4,8-双[（2-乙基己基）氧基]苯并[1,2-b]的电荷载流子产生和重组行为的影响：4,5-b'] dithiophene-2,6-diyl] [3-氟-2-[（2-乙基己基）羰基]噻吩并[3,4-b]噻吩基]]（PTB7）：[6通过转移矩阵模型（TMM）的光学模拟，线性增加电压的光致电荷提取（Photo-，-），研究了[ 6，-苯基] -C _71-丁酸甲酯（PC ₇₁ BM）有机太阳能电池（OSC）。 CELIV）技术，原子力显微镜（AFM）和Onsager-Braun模型分析。BTA2是A ₂ -A ₁ -DA ₁ -A ₂噻唑烷-2,4-二酮，BTA和茚并二噻吩作为末端受体（A ₂），桥受体（A ₁）的N型富勒烯小分子）和中央供体（D）。由于互补的吸收光谱，带有BTA2的OSC的短路电流密度可以大大提高。TMM的光学模拟表明，三元OSC的内部吸收率比不含BTA2的传统二元OSC更高，从而在三元OSC中产生更多的光生激子。光CELIV研究表明，三元OSC比二元OSC遭受更高的电荷陷阱限制的双分子重组。AFM图像显示BTA2加剧了供体和受体之间的相分离，这对电荷载流子的传输不利。Onsager-Braun模型分析证实，尽管三元OSC的电荷收集效率低于二元OSC的电荷收集效率，