Khalid Muhammad, Tariq Ayesha, Braga Ataualpa A C, Alotaibi Rajeh, Ojha Suvash Chandra
Institute of Chemistry, Khwaja Fareed University of Engineering & Information Technology, Rahim Yar Khan, 64200, Pakistan.
Centre for Theoretical and Computational Research, Khwaja Fareed University of Engineering & Information Technology, Rahim Yar Khan, 64200, Pakistan.
Sci Rep. 2024 Oct 16;14(1):24213. doi: 10.1038/s41598-024-74852-0.
Currently, polycyclic aromatic compounds in organic solar cells (OSCs) have gained substantial consideration in research communities due to their promising characteristics. Herein, polycyclic aromatic hydrocarbons (PAHs) core-based chromophores (TTFD1-TTFD6) were designed by structural modifications of peripheral acceptor groups into TTFR. The density functional theory (DFT) and time dependent density functional theory (TD-DFT) calculations were carried out at B3LYP/6-311G (d, p) functional to explore insights for their structural, electronic, and photonic characteristics. The structural modulation unveiled notable electronic impact on the HOMO and LUMO levels across all derivatives, leading to decreased band gaps. All the designed compounds exhibited band gap ranging from 2.246 to 1.957 eV, along with wide absorption spectra of 897.071-492.274 nm. An elevated exciton dissociation rate was observed due to the lower binding energy values (E = 0.381 to 0.365 eV) calculated in the derivatives compared to the reference (E = 0.394 eV). Furthermore, data from the transition density matrix (TDM) and density of states (DOS) also corroborated the effective charge transfer process. Comparable results of V for reference and designed chromophores were obtained via HOMO-LUMO. The declining V order values was noted as TTFD5 > TTFD6 > TTFD4 > TTFD3 > TTFD2 > TTFD1 > TTFR. Interestingly, TTFD5 was found with the smallest energy gap and highest absorption value, resulting in better charge transference among all the derivatives. The results illustrated that the modification in indenofluorene based chromophores with end-capped small acceptors proved to be a significant approach in achieving favorable photovoltaic properties.
目前，有机太阳能电池（OSCs）中的多环芳香族化合物因其具有前景的特性而在研究领域受到了广泛关注。在此，通过将外围受体基团结构修饰为TTFR，设计了基于多环芳烃（PAHs）核心的发色团（TTFD1-TTFD6）。采用B3LYP/6-311G (d, p)泛函进行密度泛函理论（DFT）和含时密度泛函理论（TD-DFT）计算，以探究其结构、电子和光子特性。结构调制揭示了对所有衍生物的最高占据分子轨道（HOMO）和最低未占分子轨道（LUMO）水平有显著的电子影响，导致带隙减小。所有设计的化合物的带隙范围为2.246至1.957电子伏特，同时具有897.071 - 492.274纳米的宽吸收光谱。由于与参考物（E = 0.394电子伏特）相比，衍生物中计算出较低的结合能值（E = 0.381至0.365电子伏特），观察到激子解离速率升高。此外，来自跃迁密度矩阵（TDM）和态密度（DOS）的数据也证实了有效的电荷转移过程。通过HOMO-LUMO获得了参考发色团和设计发色团的可比V值。观察到V值的下降顺序为TTFD5＞TTFD6＞TTFD4＞TTFD3＞TTFD2＞TTFD1＞TTFR。有趣的是，发现TTFD5具有最小的能隙和最高的吸收值，在所有衍生物中导致更好的电荷转移。结果表明，用封端的小受体修饰茚并芴基发色团被证明是实现良好光伏性能的重要方法。
