Computational Modelling of poly(9-vinylcarbazole)/Fullerene nanoheterojunction for organic solar cells and photovoltaics applications – A DFT Approach

Abstract

Organic polymer photovoltaics have great technological potential as an alternative source of electrical energy. The demand for inexpensive, renewable energy sources is the driving force for new approaches in the production of low-cost polymer solar cells. During the quest to determine the best deposition and thermal annealing procedures for organic materials in organic devices, it has become increasingly clear that the structural order of these materials is a key factor. Highly ordered aggregation of conjugated oligomers and polymers can improve properties such as charge transfer and interaction with light processes that lead to better device performance. The development of such procedures for polymers and their blends although successful, has taken on a substantial try-and-error approach. Structural and morphological characterization of organic materials in the solid state is relevant for their application in Organic Photovoltaics. A comprehensive investigation of the PVK/C60 adsorption surface is performed using ab initio density functional theory calculations combined with van der Waals corrections (GGA+vdW). The goal is to use detailed atomistic computational approaches to model intrinsic electrical and optical properties, to investigate the influence of packing arrangements on the anisotropy of properties that relate to device performance, to elucidate the behavior of active materials during deposition and thermal treatment impacts on resulting morphologies which are relevant to the development of devices.