The role of energy level matching in organic solar cells—Hexaazatriphenylene hexacarbonitrile as transparent electron transport material

We introduce the material hexaazatriphenylene hexacarbonitrile (HATCN) as electron conducting window layer for separating the photoactive region from the cathode in organic p–i–n type solar cells. HATCN has a wide band gap of 3.3 eV and is thus transparent in the visible range of the solar spectrum....

Full description

Saved in:
Bibliographic Details
Published in:Solar energy materials and solar cells 2011-03, Vol.95 (3), p.927-932
Main Authors: Falkenberg, Christiane, Olthof, Selina, Rieger, Ralph, Baumgarten, Martin, Muellen, Klaus, Leo, Karl, Riede, Moritz
Format: Article
Language:English
Subjects:
Applied sciences
Direct energy conversion and energy accumulation
Doping
Electrical engineering. Electrical power engineering
Electrical power engineering
Electron transport
Energy
Exact sciences and technology
HATCN
Natural energy
Organic
Photoelectric conversion
Photovoltaic conversion
Small molecule
Solar cell
Solar cells. Photoelectrochemical cells
Solar energy
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:We introduce the material hexaazatriphenylene hexacarbonitrile (HATCN) as electron conducting window layer for separating the photoactive region from the cathode in organic p–i–n type solar cells. HATCN has a wide band gap of 3.3 eV and is thus transparent in the visible range of the solar spectrum. Its electrical properties can be tuned by means of molecular n-doping which leads to an increase of electron conductivity by several orders of magnitude up to 2.2 × 10 − 4 S / cm . However, an application in photovoltaic devices is restrained by its exceptionally high electron affinity, estimated 4.8 eV, which introduces an electron injection barrier to the photoactive acceptor material C 60. Here, we present a strategy to remove this barrier by means of introducing doped and undoped C 60 intermediate layers, thus demonstrating the importance of energy level matching in a multiple layer structure and the advantages of Fermi level control by doping.
ISSN:0927-0248
1879-3398
DOI:10.1016/j.solmat.2010.11.024