Heterojunction solar cell based on donor-acceptor pi-conjugated naphthalene bisbenzimidazole, perylene bisbenzimidazole, and naphthalene imidazole: A spectroscopic, microscopic and DFT assessment.

Abstract

This study represents detailed vibrational analysis of naphthalene bisbenzimidazole (NBBI), perylene bisbenzimidazole (PBBI), and naphthalene imidazole (NI) by vibrational spectroscopic (Fourier Transform Infrared (FT-IR) and Raman), Atomic Force Microscopic (AFM) and quantum chemical studies for the first time. These sorts of compounds provide an opportunity to build potential n-type organic thin film phototransistors which can be used as organic semiconductors. Optimized molecular structures and vibrational wavenumbers of these molecules in their ground states have been calculated by Density Functional Theory (DFT) using B3LYP functional with 6-311++G(d,p) basis set. Finally, theoretical UV-Visible spectrum was predicted and Light Harvesting Efficiencies (LHE) were evaluated. AFM analysis revealed that PBBI has the highest surface roughness thus exhibits an increase in high Jsc value and high conversion efficiency.