PROJECT TITLE :

Investigation of the Blend Morphology in Bulk-Heterojunction Organic Solar Cells

ABSTRACT:

The intermixing of donor and acceptor materials within the active layer of bulk-heterojunction organic solar cells ends up in a complicated morphology. Several processes like the splitting of excitons, charge dynamics, and charge recombination are based mostly on the morphology, in explicit on the interface between the 2 materials. To boost the solar cell performance that is mainly based on these processes, two different modeling techniques are established nowadays. In drift-diffusion (DD) simulations, the common assumption is to neglect the morphology together with all interfaces and treat the active layer by one single effective material. On the contrary, kinetic Monte Carlo simulations provide a method to analyze organic solar cells considering a practical mix morphology. We have a tendency to establish a typical basis between the $64000 mix Monte Carlo simulations and DD simulations with an efficient medium approximation and compare the 2 models. Our results show that in the effective medium, the absence of native interface effects like an express treatment of the short-ranged Coulomb interaction of charges across an interface result in a difference in the charge density profile across the active layer. We tend to give hints that the effective medium approach would possibly not be sufficient to treat all internal effects induced by the blend.