Babu Numbury Surendra
Computational Quantum Chemistry Lab, Department of Chemistry, College of Natural and Mathematical Sciences, The University of Dodoma, Donoma, Tanzania.
ChemistryOpen. 2022 Feb;11(2):e202100273. doi: 10.1002/open.202100273.
The new donor-acceptor-donor (D-A-D) monomers have been studied using density functional theory (DFT) and time-dependent density functional theory (TD-DFT) methods to evaluate the optoelectronic and electronic properties for bulk heterojunction (BHJ) organic solar cells. The TD-DFT method is combined with a hybrid exchange-correlation functional using the B3LYP method in conjunction with a polarizable continuum model (PCM) and a 6-311G basis set to predict the excitation energies and absorption spectra of all monomers. The predicted bandgap (E ) of the monomers decreasing in the following order D1<D2<D3<D4<D5<D6<D7<D9<D8. Furthermore, open-circuit voltage (V ) estimates for monomers with [6,6]-phenyl-C71-butyric acid methyl ester (PC71BM) acceptor. The V of the studied monomers ranges from 0.976 to 1.398 eV in the gas and from 1.109 to 1.470 eV in the solvent phase with PC71BM acceptor, which is sufficient for efficient electron injection into the acceptor's LUMO. The results show that theoretically, a maximum energy conversion efficiency of roughly 5 % for D8 and 5.8 5 % for D7.
已使用密度泛函理论（DFT）和含时密度泛函理论（TD-DFT）方法对新型给体-受体-给体（D-A-D）单体进行了研究，以评估体异质结（BHJ）有机太阳能电池的光电和电子性质。TD-DFT方法与采用B3LYP方法的杂化交换相关泛函相结合，同时结合极化连续介质模型（PCM）和6-311G基组，以预测所有单体的激发能和吸收光谱。预测的单体带隙（E）按以下顺序减小：D1<D2<D3<D4<D5<D6<D7<D9<D8。此外，还对含有[6,6]-苯基-C71-丁酸甲酯（PC71BM）受体的单体进行了开路电压（V）估算。在所研究的单体中，在气相中V的范围为0.976至1.398 eV，在含有PC71BM受体的溶剂相中V的范围为1.109至1.470 eV，这足以实现向受体最低未占分子轨道（LUMO）的有效电子注入。结果表明，从理论上讲，D8的最大能量转换效率约为5%，D7的最大能量转换效率约为5.85%。
