In this work, a series of six organic dyes-sensitized solar cells (DSSCs) combining various π-bridges with a fixed donor (triphenylamine) and a fixed electron acceptor (cyanoacrylic acid), namely D1-6, were studied. The geometrical structure, electronic and optical properties of these dyes have been investigated with the density functional theory and TD-BHandHLYP hybrid functional (time-dependent Becke-Half-and-Half-Lee–Yang–Parr’s) methods. The effects of π-bridging of the dyes have shown that the rings with a sulfur atom reduce the energy gaps and provide a redshift of the absorption spectra. Similarly, we focus on the description of the ground and excited state properties. On the other hand, the pyrrole group improves the open-circuit voltage (V_OC) and the light-harvesting efficiency parameters leading to greater power conversion efficiency. Furthermore, the results revealed lowest total reorganization energy λ (λ⁺ and λ⁻) for the dye D3 with pyrrole linkage, which reflects its most favorable charge-transport properties, implying a lower charge recombination rate, faster charge injection and dye regeneration processes. Therefore, this study would provide a new path to design novel conjugated organic molecules as dyes for high-performance DSSCs.

在这项工作中，研究了一系列六个有机染料敏化太阳能电池（DSSC），它们将各种π桥与一个固定的供体（三苯胺）和一个固定的电子受体（氰基丙烯酸），即D 1-6结合在一起。这些染料的几何结构，电子和光学性质已通过密度泛函理论和TD-BHandHLYP杂化泛函（与时间有关的Becke-Half-and-Half-Lee-Yang-Parr法）进行了研究。染料的π桥连效应表明，带有硫原子的环减少了能隙，并提供了吸收光谱的红移。同样，我们专注于基态和激发态特性的描述。另一方面，吡咯基团改善了开路电压（V _OC）和光收集效率参数导致更高的功率转换效率。此外，结果显示最低的总重组能λ（λ ⁺和λ ^- ）用于染料d 3与吡咯联动，体现其最有利的电荷传输性质，这意味着较低的电荷复合率，更快的电荷注入和染料再生过程。因此，这项研究将为设计新型共轭有机分子作为高性能DSSC的染料提供一条新途径。