From Molecular Packing Structures to Electronic Processes: Theoretical Simulations for Organic Solar Cells

Molecular packing structures in the active layers have a crucial impact on the electronic processes for organic solar cells. To date, however, it is still difficult to probe molecular self-assembling and packing structures at the atomic level by experimental techniques, which is hindering reliable understanding of the structure-property relationship. Accordingly, theoretical simulations provide a useful tool and are becoming more and more important. Here, recent advances in theoretical simulations for organic solar cells are reviewed. First, a brief introduction of theoretical methodologies, including the strategies of molecular dynamics simulations of active-layer processing procedures and quantum-chemical methods for calculating electron transfer processes, is given. Then, the influences of molecular packing structures on charge generation, charge recombination, and charge transport are analyzed and discussed from a theoretical perspective. Finally, prospects and challenges are pointed out for theoretical prediction of the electrical characteristics and photoelectric conversion efficiencies of organic solar cells from molecular structures.