Modulating triphenylamine-based organic dyes for their potential application in dye-sensitized solar cells: a first principle theoretical study.

By using computational methodologies based on time dependent density functional theory (TDDFT) we study the opto-electronic properties of three types of triphenylamine (TPA)-based dyes, namely TPA-TBT-1, TPA-DBT-1, and TPA-BT-1, and these are proposed as potential candidates for photovoltaic applications. Energy band modulation has been performed by functionalizing these dyes with different electron donating and electron withdrawing groups. Photoelectron spectra and photovoltaic properties of the dyes have been investigated by a combination of DFT and TDDFT approaches. Based on the optimized molecular geometry, relative position of the frontier energy levels, and the absorption maximum of the dyes we propose some dyes offering good photovoltaic performance. At the same time, these results provide a direction for optimizing the composition of dye-metal surface nanodevices for fabricating dye-sensitized solar cells (DSSCs).