Inverted bulk-heterojunction solar cell with cross-linked hole-blocking layer

Yasemin Udum; Patrick Denk; Getachew Adam; Dogukan H Apaydin; Andreas Nevosad; Christian Teichert; Matthew S White; Niyazi S Sariciftci; Markus C Scharber

doi:10.1016/j.orgel.2014.02.009

Inverted bulk-heterojunction solar cell with cross-linked hole-blocking layer

Org Electron. 2014 May;15(5):997-1001. doi: 10.1016/j.orgel.2014.02.009.

Authors

Yasemin Udum¹, Patrick Denk², Getachew Adam², Dogukan H Apaydin², Andreas Nevosad³, Christian Teichert³, Matthew S White², Niyazi S Sariciftci², Markus C Scharber²

Affiliations

¹ Institute for Organic Solar Cells, Johannes Kepler University Linz, Altenbergerstrasse 69, 4040 Linz, Austria ; Institute of Science and Technology, Department of Advanced Technologies, Gazi University, 06570 Ankara, Turkey.
² Institute for Organic Solar Cells, Johannes Kepler University Linz, Altenbergerstrasse 69, 4040 Linz, Austria.
³ Institute of Physics, Montanuniversitaet Leoben, Franz-Josef-Straße 18, 8700 Leoben, Austria.

Abstract

We have developed a hole-blocking layer for bulk-heterojunction solar cells based on cross-linked polyethylenimine (PEI). We tested five different ether-based cross-linkers and found that all of them give comparable solar cell efficiencies. The initial idea that a cross-linked layer is more solvent resistant compared to a pristine PEI layer could not be confirmed. With and without cross-linking, the PEI layer sticks very well to the surface of the indium-tin-oxide electrode and cannot be removed by solvents used to process PEI or common organic semiconductors. The cross-linked PEI hole-blocking layer functions for multiple donor-acceptor blends. We found that using cross-linkers improves the reproducibility of the device fabrication process.

Keywords: Device design; Electrical contact; Organic solar cell; Stability.