A series of twelve Acceptor-π-Donor-π-Acceptor (A-π-D-π-A) topology-based donor molecules, where diketopyrrolopyrrole (DPP) as donor core unit is connected through furan which acts as conjugated π-bridge (CB) to aromatic derivatives (Ar) as acceptor units, have been investigated by making substitutions in acceptor units by using density functional theory(DFT) and time-dependent density functional theory (TD-DFT) for organic solar cell applications. The comparative study of optoelectronic properties indicates that thiadiazole with pyridine units containing molecules (M6b) exhibit lower energy of highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels than those of oxadiazole and pyridine containing units (M6b). Among our investigated donors, the smallest Eg of 1.60 eV was observed for both M6a and M6b with distinctive broad absorption at 843 and 857 nm, respectively. Overall, smaller electron transfer (λ_e) values in contrast to hole transfer (λ_h) demonstrate that these donor compounds would be best for λ_e. The calculated open circuit voltage (Voc) is 2.45 and 2.17 eV, regarding bisPCBM and PC60BM (phenyl-C61-butyric acid methyl ester) acceptors. Thus, these theoretical calculations not only endorse the deep consideration between the chemical structures and optoelectronic characteristics of the donor-acceptor systems but also suggest appropriate materials for high-performance Organic Photovoltaics (OPV).

Graphical abstract

中文翻译：

---

不同芳族共轭桥对基于二酮吡咯并吡咯的有机光伏光电材料的影响。

一系列十二个基于受体-π-供体-π-受体（A-π-D-π-A）拓扑的供体分子，其中作为供体核心单元的二酮吡咯并吡咯（DPP）通过呋喃连接，呋喃充当共轭π桥（CB）以芳香族衍生物（Ar）为受体单元，已经通过使用密度泛函理论（DFT）和时变密度泛函理论（TD-DFT）在有机太阳能电池应用中对受体单元进行取代来研究。光电性能的比较研究表明，与含恶二唑和吡啶的单元（M6b）相比，具有含吡啶单元的分子（M6b）的噻二唑的最高占据分子轨道（HOMO）能量水平最低，而未占据分子轨道（LUMO）的能量水平最低。在我们调查的捐赠者中，最小的Eg为1。M6a和M6b均观察到60 eV，分别在843和857 nm处具有明显的宽吸收。总体而言，较小的电子转移（λ_È）相比于空穴传输（λ值_ħ）证明这些给体化合物将是最适合λ _ë。对于bisPCBM和PC60BM（苯基-C61-丁酸甲酯）受体，计算得出的开路电压（Voc）为2.45和2.17 eV。因此，这些理论计算不仅支持供体-受体系统的化学结构与光电特性之间的深入考虑，而且还为高性能有机光伏（OPV）提供了合适的材料。

图形概要