May 24, 2019 Journal article Open Access

Modeling the morphology evolution of organic solar cells

Bergermann, Kai

This Upload contains python code as well as simulation results supplementing the article 'Modeling the morphology evolution of organic solar cells' submitted to GAMM Archive for Students.

Abstract of the article:

Organic solar cells present a promising alternative for the generation of solar energy at lower material and production costs compared to widely used silicon-based solar cells. The major drawback of organic solar cells currently is a lower rate of energy conversion. Thus many research projects aim to improve the achievable efficiency.

In this work a phase field model is used to mathematically describe the morphology evolution of the active layer composed of polymer as electron-donor and fullerene as electron-acceptor. The derivation of a chemical potential term and a surface energy term for the polymer-fullerene solution using the Flory-Huggins theory forms the basis to employ the Cahn-Hilliard equation. After including several specifics of the application in this non-linear partial differential equation of fourth order, an implementation of the model using the FEM solver software FEniCS provides some simulation results that qualitatively match results from the literature.