Document Server@UHasselt >
Research >
Research publications >

Please use this identifier to cite or link to this item: http://hdl.handle.net/1942/10882

Title: Relating the open-circuit voltage to interface molecular properties of donor:acceptor bulk heterojunction solar cells
Authors: VANDEWAL, Koen
Tvingstedt, Kristofer
Inganas, Olle
Issue Date: 2010
Citation: PHYSICAL REVIEW B, 81(12)
Abstract: The open-circuit voltage (V-oc) of polymer:fullerene bulk heterojunction solar cells is determined by the interfacial charge-transfer (CT) states between polymer and fullerene. Fourier-transform photocurrent spectroscopy and electroluminescence spectra of several polymer:fullerene blends are used to extract the relevant interfacial molecular parameters. An analytical expression linking these properties to V-oc is deduced and shown to be valid for photovoltaic devices comprising three commonly used conjugated polymers blended with the fullerene derivative [6,6]-phenyl-C61-butyric acid methyl ester (PCBM). V-oc is proportional to the energy of the CT states E-CT. The energetic loss q Delta V between E-CT and qV(oc) vanishes when approaching 0 K. It depends linearly on T and logarithmically on illumination intensity. Furthermore q Delta V can be reduced by decreasing the electronic coupling between polymer and fullerene or by reducing the nonradiative recombination rate. For the investigated devices we find a loss q Delta V of similar to 0.6 eV at room temperature and under solar illumination conditions, of which similar to 0.25 eV is due to radiative recombination via the CT state and similar to 0.35 eV is due to nonradiative recombination.
Notes: [Vandewal, Koen; Tvingstedt, Kristofer; Inganas, Olle] Linkoping Univ, COE, Dept Phys Chem & Biol, S-58183 Linkoping, Sweden. [Vandewal, Koen; Gadisa, Abay; Manca, Jean V.] Hasselt Univ, IMEC IMOMEC, B-3590 Diepenbeek, Belgium. [Vandewal, Koen; Gadisa, Abay; Manca, Jean V.] Hasselt Univ, Inst Mat Res, B-3590 Diepenbeek, Belgium. koeva@ifm.liu.se
URI: http://hdl.handle.net/1942/10882
DOI: 10.1103/PhysRevB.81.125204
ISI #: 000276248900077
ISSN: 1098-0121
Category: A1
Type: Journal Contribution
Validation: ecoom, 2011
Appears in Collections: Research publications

Files in This Item:

There are no files associated with this item.

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.