Kushwaha Pankaj Kumar, Srivastava Sunil Kumar
Department of Physics, School of Physical Sciences, Mahatma Gandhi Central University, Motihari, East Champaran, Bihar, 845401, India.
J Mol Model. 2024 Sep 30;30(10):356. doi: 10.1007/s00894-024-06159-w.
Indandione-based materials are promising candidates for organic electronics, offering high electron mobility and tunable optoelectronic properties. In this study, we explore the optoelectronic and photovoltaic properties of indandione-based donor-acceptor (D-A) materials, specifically (R1) and (R2), by introducing malononitrile group acceptors into their molecular structure. These strong electron-withdrawing acceptors are designed to enhance charge transfer and overall material performance. The designed molecules (DM1-DM4) exhibit a low optical band gap of approximately 1.77 eV, significantly lower than the reference materials (R1 and R2) at around 2.24 eV in a solvent environment. Among the designed molecules, DM4 stands out with superior photovoltaic parameters, including a narrow optical band gap (1.77 eV), higher electron affinity (3.49 eV), an extended excited state lifetime (10.0 ns) owing to its low electron and hole reorganization energies (λ ~ 0.13 eV and λ ~ 0.24 eV), and improved short-circuit current density (J) of ~ 15.73 mA/cm. Notably, DM4 achieves a power conversion efficiency (PCE) of ~ 18.5%, making it an excellent candidate for device applications.
A comprehensive computational investigation was carried out on indandione-based D-A materials with malononitrile group acceptors (DM1-DM4) using density functional theory (DFT) and time-dependent DFT (TD-DFT) methods, as implemented in Gaussian 16 software. We examined the electronic and optical properties of the proposed molecules through frontier molecular orbital (FMO) analysis, UV-Vis absorption spectra, density of states (DOS), exciton binding energy (E), and transition density matrix (TDM) analysis, utilizing GaussView 6.0 and Multiwfn 3.8 software. The photovoltaic parameters and power conversion efficiency (PCE) were evaluated using the Scharber and Alharbi models.
基于茚二酮的材料是有机电子学领域颇具潜力的候选材料，具有高电子迁移率和可调节的光电特性。在本研究中，我们通过将丙二腈基团受体引入茚二酮基供体 - 受体（D - A）材料（具体为（R1）和（R2））的分子结构中，探索其光电和光伏特性。这些强吸电子受体旨在增强电荷转移和整体材料性能。所设计的分子（DM1 - DM4）在溶剂环境中表现出约1.77 eV的低光学带隙，明显低于参考材料（R1和R2）在约2.24 eV时的带隙。在所设计的分子中，DM4具有出色的光伏参数，包括窄光学带隙（1.77 eV）、更高的电子亲和力（3.49 eV）、由于其低电子和空穴重组能（λ ~ 0.13 eV和λ ~ 0.24 eV）而具有的延长激发态寿命（10.0 ns）以及约15.73 mA/cm的改善短路电流密度（J）。值得注意的是，DM4实现了约18.5%的功率转换效率（PCE），使其成为器件应用的优秀候选材料。
使用高斯16软件中实现的密度泛函理论（DFT）和含时密度泛函理论（TD - DFT）方法，对含有丙二腈基团受体的茚二酮基D - A材料（DM1 - DM4）进行了全面的计算研究。我们利用GaussView 6.0和Multiwfn 3.8软件，通过前沿分子轨道（FMO）分析、紫外 - 可见吸收光谱、态密度（DOS）、激子结合能（E）和跃迁密度矩阵（TDM）分析，研究了所提出分子的电子和光学性质。使用Scharber和Alharbi模型评估了光伏参数和功率转换效率（PCE）。
