Enhancement of highly efficient flavone-based organic dyes with different anchoring groups effect in dye-sensitized solar cells using experimental and TD-DFT study

Three D-π-A-based flavone organic dyes (R1, R2 and R3) were designed and characterized used as sensitizers for dye-sensitized solar cells (DSSCs) application. In this work, theoretical electronic structure and optical absorption spectra are analyzed in the different solvent phases and investigated using the density functional theory (DFT) and time-dependent DFT (TD-DFT) calculations at the B3LYP/6–311++G(d,p) level of theory. These findings were supported by the results from cyclic voltammetry (CV), Fourier transform infrared spectroscopy (FT-IR), Scanning electron microscopy (SEM), electrochemical impedance spectroscopy (EIS), galvanostatic charging and discharging (GCD). The highest power conversion efficiency (PCE) of R2 dye exhibit is 2.09% with a high JSC\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$J_{SC}$$\end{document} value of 8.82 mA.cm−2, VOC\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$V_{OC}$$\end{document} of 0.37 V and FF of 0.48, respectively. These results suggest that the molecular design has high performance for organic photovoltaic (PV) solar cells, and this research work will pave the way for the design of efficient flavone-based organic dye sensitizers.