We report on the theoretical design of five new organic D−π−A sensitizers (JA1‒JA5) featuring silole and selenophene space π‒linker, and an evaluation of their performance for application in dye-sensitized solar cells (DSSCs). Their structural, spectral and electronic properties were investigated using density functional theory (DFT) and time-dependent (TD)-DFT calculations. We found that incorporation of a silole as a π‒bridge substituent in the five-membered heterocyclic dye, in particular to JA2 and JA4, remarkably improves the optical UV–Vis absorption spectra and achieves larger light-harvesting efficiency (LHE) relative to the conventional thiophene-based spacer (JA1), leading to a larger J_sc response. Interaction of these two theoretically designed dyes JA2 and JA4 in combination with iodide electrolytes was calculated and the LHE is significantly larger than that of their isolated dyes, both contribute to improving the DSSC performance. Calculated results give insight into the optoelectronic properties of the rationally substituted π-spacer D−π−A sensitizers concerning their regeneration and applicability for DSSCs.

我们报告了五种新型的有机D-π-A敏化剂（JA1 ‒ JA5）的理论设计，这些敏化剂具有甲硅烷基和硒烯空间π接头，并评估了它们在染料敏化太阳能电池（DSSC）中的应用性能。使用密度泛函理论（DFT）和时变（TD）-DFT计算研究了它们的结构，光谱和电子性质。我们发现噻咯如在五元杂环的染料的π桥取代基的那掺入，特别是JA2和JA4，显着地提高了光的UV-Vis吸收光谱，并实现相对于较大的捕光效率（LHE）传统的基于噻吩的间隔基（JA1），导致更大的J_sc响应。这两个设计理论上的染料的相互作用JA2和JA4在用碘化电解质组合计算和LHE比其分离染料的显著较大，既有助于改善DSSC的性能。计算结果使人们深入了解了合理取代的π-间隔物D-π-A敏化剂的光电性能，涉及它们的再生和对DSSC的适用性。