The Influence of Morphology on the Charge Transport in Two-Phase Disordered Organic Systems. Issue 1737 (20th May 2015)

• Record Type: Journal Article
• Authors: Woellner, Cristiano F.; Machado, Leonardo D.; Autreto, Pedro A. S.; Freire, José A.; Galvão, Douglas S.
• Editors: Facchetti, A.
• Is Part Of: MRS proceedings. Issue 1737:(2015)
• Publication Date: 2015-05-20
• Subjects: blend, -- morphology, -- photovoltaic; Electrical engineering -- Congresses; Physics -- Congresses; Materials -- Research -- Congresses; Materials science -- Congresses; 620.11
• DOI: 10.1557/opl.2015.502
• Languages: English
• ISSNs: 0272-9172

Abstract

ABSTRACT: In this work we use a three-dimensional Pauli master equation to investigate the charge carrier mobility of a two-phase system, which can mimic donor-acceptor and amorphous-crystalline bulk heterojunctions. Our approach can be separated into two parts: the morphology generation and the charge transport modeling in the generated blend. The morphology part is based on a Monte Carlo simulation of binary mixtures (donor/acceptor). The second part is carried out by numerically solving the steady-state Pauli master equation. By taking the energetic disorder of each phase, their energy offset and domain morphology into consideration, we show that the carrier mobility can have a significant different behavior when compared to a one-phase system. When the energy offset is non-zero, we show that the mobility electric field dependence switches from negative to positive at a threshold field proportional to the energy offset. Additionally, the influence of morphology, through the domain size and the interfacial roughness parameters, on the transport was also investigated.