Utilizing Energy Transfer in Binary and Ternary Bulk Heterojunction Organic Solar Cells
Artikel i vetenskaplig tidskrift, 2016

Energy transfer has been identified as an important process in ternary organic solar cells. Here, we develop kinetic Monte Carlo (KMC) models to assess the impact of energy transfer in ternary and binary bulk heterojunction systems. We used fluorescence and absorption spectroscopy to determine the energy disorder and Forster radii for poly(3-hexylthiophene-2,5-diyl), [6,6]-phenyl-C61-butyric acid methyl ester, 4-bis[4-(N,N-diisobutylamino)-2,6-dihydroxyphenyl]squaraine (DIBSq), and poly(2,5-thiophene-alt-4,9-bis(2-hexyldecyl)-4,9-dihydrodithieno[3,2-c:3 ',2'-h][1,5]naphthyridine-5,10-dione). Heterogeneous energy transfer is found to be crucial in the exciton dissociation process of both binary and ternary organic semiconductor systems. Circumstances favoring energy transfer across interfaces allow relaxation of the electronic energy level requirements, meaning that a cascade structure is not required for efficient ternary organic solar cells. We explain how energy transfer can be exploited to eliminate additional energy losses in ternary bulk heterojunction solar cells, thus increasing their open-circuit voltage without loss in short-circuit current. In particular, we show that it is important that the DIBSq is located at the electron donor acceptor interface; otherwise charge carriers will be trapped in the DIBSq domain or excitons in the DIBSq domains will not be able to dissociate efficiently at an interface. KMC modeling shows that only small amounts of DIBSq (<5% by weight) are needed to achieve substantial performance improvements due to long-range energy transfer.

energy level optimization

Monte Carlo

ternary organic solar cells

binary photovoltaic

exciton dissociation

energy transfer

Författare

K. Feron

CSIRO Energy Flagship

University of Newcastle, Australia

J. M. Cave

University of Bath

M. N. Thameel

University of Newcastle, Australia

University Of Anbar

C. O'Sullivan

University of Newcastle, Australia

Renee Kroon

Chalmers, Kemi och kemiteknik, Tillämpad kemi, Polymerteknologi

Mats Andersson

Chalmers, Kemi och kemiteknik, Tillämpad kemi, Polymerteknologi

X. J. Zhou

University of Newcastle, Australia

C. J. Fell

CSIRO Energy Flagship

W. J. Belcher

University of Newcastle, Australia

A. B. Walker

University of Bath

P. Dastoor

University of Newcastle, Australia

ACS Applied Materials & Interfaces

1944-8244 (ISSN) 1944-8252 (eISSN)

Vol. 8 20928-20937

Ämneskategorier

Materialteknik

Subatomär fysik

DOI

10.1021/acsami.6b05474

PubMed

27456294