Al-Temimei Faeq A, Awayiz Muntadher Talib, Abbood Hamid I
Department of Physics, Collage of Sciences, University of Kufa, Najaf, Iraq.
Al-Zahraa University for Women, Karbala, Iraq.
J Fluoresc. 2024 Sep 14. doi: 10.1007/s10895-024-03936-x.
The performance and efficacy of dyes, which are crucial photon-harvesting components in dye-sensitized solar cells (DSSCs), must be meticulously analysed at the molecular level. This research focuses on a theoretical investigation of dye characteristics rather than the synthesis of novel compounds. Using Density Functional Theory (DFT) and Time-Dependent DFT (TD-DFT), we have analysed six D-π-A structure dyes designed with pyrene as the π-bridge and various functional groups as donors. Our study examines their geometrical, electronic, optical, electronic localization, and electrochemical properties. The findings reveal that these theoretically designed D-π-A dyes show significant improvements in light-harvesting efficiency, open-circuit photovoltage, electron injection efficiency, and overall photovoltaic performance. The analysis indicates effective electron injection from each dye into the conduction band of TiO, followed by efficient regeneration and enhanced intra- and intermolecular charge transfer properties. The incorporation of pyrene as a π-bridge and the use of different functional groups as donors are crucial for facilitating electron transfer from the donor to the acceptor region. Among the dyes studied, the D-π-D modified dye demonstrates superior theoretical performance, attributed to its higher energy levels of the lowest unoccupied molecular orbital and greater oscillator strengths for excited states. This results in improved intramolecular electron transfer and electron injection into the conduction band of TiO, followed by effective regeneration. Overall, our study highlights the potential of these theoretically modeled dyes as highly promising sensitizers for DSSCs, due to their exceptional optical and electronic properties and impressive photovoltaic parameters. These findings position these molecular structures as strong candidates for future applications in organic DSSCs.
染料作为染料敏化太阳能电池（DSSC）中至关重要的光子捕获组件，其性能和功效必须在分子层面进行细致分析。本研究聚焦于染料特性的理论研究，而非新型化合物的合成。利用密度泛函理论（DFT）和含时密度泛函理论（TD-DFT），我们分析了六种以芘为π桥、各种官能团为供体设计的D-π-A结构染料。我们的研究考察了它们的几何、电子、光学、电子局域化和电化学性质。研究结果表明，这些理论设计的D-π-A染料在光捕获效率、开路光电压、电子注入效率和整体光伏性能方面有显著提升。分析表明，每种染料都能有效地将电子注入TiO的导带，随后进行高效再生，并增强分子内和分子间的电荷转移性质。引入芘作为π桥以及使用不同官能团作为供体对于促进电子从供体向受体区域转移至关重要。在所研究的染料中，D-π-D修饰染料表现出卓越的理论性能，这归因于其最低未占据分子轨道的能级较高以及激发态的振子强度更大。这导致分子内电子转移和电子注入TiO导带得到改善，随后进行有效再生。总体而言，我们的研究突出了这些理论建模染料作为DSSC极具潜力的敏化剂的潜力，因其具有出色的光学和电子性质以及令人印象深刻的光伏参数。这些发现使这些分子结构成为未来有机DSSC应用的有力候选者。
