Electronic and Photovoltaic Properties of Modified Cycloparaphenylene Dyes: A DFT and TD-DFT Study

This study investigates a new series of cycloparaphenylene based dyes for photovoltaic applications. The parent CPP-1 molecule was modified by introducing phenyl ethylene units (CPP-2 to CPP-4) and an indacene fragment (CPP-5) to tune its electronic and optical properties The electronic structures and photophysical behavior were examined using DFT and TDDFT at the B3LYP level. Calculations employed SDD for all systems. Key parameters, including geometries, frontier orbital energies, energy gaps, uv visible spectra, density of states and photovoltaic properties, were analyzed. Results indicate that excitation facilitates transport of electrons to the conduction band from the dyes, suggesting efficient charge injection. The modified dyes show improved electronic coupling and enhanced photoelectric performance compared to CPP-1. These results demonstrate the possibility of cycloparaphenylene functionalization as a method for creating effective organic dyes for solar cells that are dye-sensitized.