Scalable PbS Quantum Dot Solar Cell Production by Blade Coating from Stable Inks
Nataliia Sukharevska, Dmytro Bederak, Vincent M. Goossens, Jamo Momand, Herman Duim, Dmitry N. Dirin, Maksym V. Kovalenko, Bart J. Kooi, Maria Antonietta Loi
Abstract
in 2,6-difluoropyridine (DFP), we obtained inks that are colloidally stable for more than 3 months. Furthermore, we demonstrated that DFP yields stable dispersions even of large diameter PbS QDs, which are of great practical relevance owing to the extended coverage of the near-infrared region. The optimization of blade-coating deposition of DFP-based inks enabled the fabrication of PbS QD solar cells with power conversion efficiencies of up to 8.7%. It is important to underline that this performance is commensurate with the devices made by spin coating of inks with the same ligands. A good shelf life-time of these inks manifests itself in the comparatively high photovoltaic efficiency of 5.8% obtained with inks stored for more than 120 days.