Solvent effect on the efficiency of triphenylamine-based dye-sensitized
solar cells, molecular approach
Abstract
In this research, dynamics, and kinetics of some metal-free organic dyes
based on triphenylamine having a D-π-A type structure were investigated
in the gas phase and solvent (ethanol, dichloromethane, toluene,
tetrahydrofuran, chloroform, and dimethylformamide) using the quantum
chemistry calculations. These structures consist of triphenylamine as
the donor linked to the acceptor units of cyanoacrylic acid and benzoic
acid via different π-conjugated systems. The obtained results show that
TC601 dye having the ethynyl anthracene phenyl -conjugated system has
the preferred charge/hole transfer properties (Ginj/Greg), which in
ethanol as the solvent, the lowest values of Ginj and Greg were
evaluated. Molecular spectroscopic properties of the studied dyes reveal
that H-P and F-P dyes have favorable molar absorption coefficients in
all media. Also, the behaviors of the light-harvesting efficiency (LHE)
and incident photon to current efficiency (IPCE) as the functions of the
wavelength were analyzed, which show that the presence of solvent
increases the values of IPCE and LHE for most studied dyes in comparison
with the gas phase. Finally, based on different analyses, TC601 as the
dye and ethanol as the solvent are proposed as the preferred candidates
to be applied in the DSSCs.