Computational Investigations on Acceptor Substituent Influence of Metal-free Efficient Chromophores for Optoelectronic Properties

Abstract

Abstract In this study, the computational studies of the PO3H2, CONHOH and SO2H (A1-A3) molecules were investigated for optoelectronic applications on the basis of tetrahydroquinoline (C1-1) dye. Besides, a detailed calculation of the molecular structures, energy levels, driving force of injection, regeneration, Non-linear optical (NLO) property, chemical hardness, excitation binding energy, light-harvesting efficiency (LHE), absorption spectra and photovoltaic (PV) parameters were all discussed in details using density functional theory (DFT) and time-dependent DFT (TD-DFT) methods. The optoelectronic properties of C1-1 based A1-A3 molecules are originated to be tuned by changing the position of the acceptor. To get a maximum absorption spectrum of C1-1, Becke’s three-parameter and Lee-Yang-Parr (B3LYP), coulomb-attenuating method-B3LYP (CAM-B3LYP) and Head-Gordon model (ωB97XD) were used for the TD-DFT method. Results reveal that the TD-ɷB97XD and 6-31G(d) combined functionals were provided reliable effects to the C1-1. Therefore, absorption spectra of the A1-A3 dyes were followed by the TD-ɷB97XD/6-31G(d) techniques. The designed A1 (PO3H2) dye displayed a smaller energy gap and red-shifted broadened spectra than the other dyes and C1-1, it can be utilized to get a better PV properties. In addition, NLO properties of the A1-A3 chromophores were calculated by the polarizability and first-order hyperpolarizability. Consequently, A1 dye has a superior value of the NLO activity. This study will deliver a valuable reference to the upcoming molecular proposal of tetrahydroquinoline dyes for optoelectronic applications.