posted on 2022-01-27, 00:44authored byDuvalier Madrid-Úsuga, Alejandro Ortiz, John H. Reina
Solar cells based
on organic compounds are a proven emergent alternative
to conventional electrical energy generation. Here, we provide a computational
study of power conversion efficiency optimization of boron dipyrromethene
(BODIPY) derivatives by means of their associated open-circuit voltage,
short-circuit density, and fill factor. In doing so, we compute for
the derivatives’ geometrical structures, energy levels of frontier
molecular orbitals, absorption spectra, light collection efficiencies,
and exciton binding energies via density functional theory (DFT) and
time-dependent (TD)-DFT calculations. We fully characterize four D−π–A
(BODIPY) molecular systems of high efficiency and improved Jsc that are well suited for integration into
bulk heterojunction (BHJ) organic solar cells as electron-donor materials
in the active layer. Our results are twofold: we found that molecular
complexes with a structural isoxazoline ring exhibit a higher power
conversion efficiency (PCE), a useful result for improving the BHJ
current, and, on the other hand, by considering the molecular systems
as electron-acceptor materials, with P3HT as the electron donor in
the active layer, we found a high PCE compound favorability with a
pyrrolidine ring in its structure, in contrast to the molecular systems
built with an isoxazoline ring. The theoretical characterization of
the electronic properties of the BODIPY derivatives provided here,
computed with a combination of ab initio methods and quantum models,
can be readily applied to other sets of molecular complexes to hierarchize
optimal power conversion efficiency.