QSPR Study of 2-Hydroxy-1,4-Napthoquinone Derivatives for the Dye Sensitized Solar Cell Applications: A Density Functional Theory Approach

Dye sensitizers play an important role in dye sensitized solar cell (DSSC) for harvesting the solar energy. Hence, major requirement for this is that the dye molecule should absorb wider spectrum of the visible region with a smaller band gap. The present work constitutes a QSPR analysis to design a novel material with enhanced maximum absorption at longer wavelength (lambda(max)) in the visible region by substituting electron donating and-withdrawing substituents. 2-hydroxy-1,4-napthoquinone (laws one) is modified by single and multiple substitutions of electron-donating (-NH2,-O- and -OH), electron-withdrawing (-CN) and combination of the donor-acceptor test groups to enhance the absorption at longer lambda(max). These derivatives of laws one are studied by TD-DFT approach in ethanol solvent using polarizable continuum model at PBE1PBE/6-311+G(d,p) level of theory. The study has revealed that the electron-donating groups substituted at various positions of the molecular rings enhance lambda(max) at longer wavelength in the visible region. On the other hand, it is also observed that the electron-withdrawing group does not change lambda(max) significantly. Among the electron-donor groups, the substitution of moderate electron donating group (-OH) gives notable shift to longer lambda(max) of laws one by 134 nm and the strongest electron-donor (-O-) is observed to give maximum shift to longer lambda(max) of laws one by 230 nm. Whereas, the combination of electron-donating (-O-) and-withdrawing group (-CN) substitutions shift the lambda(max) by 312 nm to the higher side and extend it upto 700.6 nm. Furthermore, these findings are analyzed with the difference between HOMO and LUMO energies of the studied moieties. The study has demonstrated that such type of QSPR analysis can significantly improve the absorption activity towards longer wavelength to design the novel material with enhanced optoelectronic properties.