Watching Space Charge Build Up in an Organic Solar Cell

A1 Originalartikel i en vetenskaplig tidskrift (referentgranskad)

Interna författare/redaktörer

Publikationens författare: Sebastian Wilken, Oskar J. Sandberg, Dorothea Scheunemann, Ronald Österbacka
Förläggare: WILEY-VCH Verlag GmbH & Co. KGaA
Förlagsort: Weinheim
Publiceringsår: 2020
Tidskrift: Solar Rrl
Tidskriftsakronym: solar-rrl
Volym: 2020
Nummer: 4
Artikelns första sida, sidnummer: 1
Artikelns sista sida, sidnummer: 8
eISSN: 2367-198X


Space charge effects can significantly degrade charge collection in organic
photovoltaics (OPVs), especially in thick-film devices. The two main causes
of space charge are doping and imbalanced transport. Although these are
completely different phenomena, they lead to the same voltage dependence
of the photocurrent, making them difficult to distinguish. Herein, a method is
introduced on how the build-up of space charge due to imbalanced transport can
be monitored in a real operating organic solar cell. The method is based on the
reconstruction of quantum efficiency spectra and requires only optical input
parameters that are straightforward to measure. This makes it suitable for the
screening of new OPV materials. Furthermore, numerical and analytical means
are derived to predict the impact of imbalanced transport on charge collection. It
is shown that when charge recombination is sufficiently reduced, balanced
transport is not a necessary condition for efficient thick-film OPVs.

Senast uppdaterad 2020-05-06 vid 04:30