1 Department of Energy Conversion and Storage, Technical University of Denmark2 Functional organic materials, Department of Energy Conversion and Storage, Technical University of Denmark3 Friedrich‐Alexander University Erlangen‐Nuremberg4 BASF5 Merck Chemicals Ltd.6 Polyera Corporation7 BASF
Owing to the lack of scalable high performance donor materials, studies on mass-produced organic photovoltaic (OPV) devices lag far behind that on lab-scale devices. In this work, we choose 6 already commercially available conjugated polymers and systematically investigate their potential in organic tandem solar cells. All the devices are processed under environmental conditions using doctor-blading, which is highly compatible with mass-production coating technologies. Power conversion efficiencies (PCE) of 6–7% are obtained for OPV devices based on different active layers. Optical simulations based on experimental data are performed for all realized tandem solar cells. An efficiency potential of ∼10% is estimated for these compounds in combination with phenyl-C61-butyric acid methyl ester (PCBM) as an acceptor. In addition, we assume a hypothetical, optimized acceptor to understand the limitation of donors. It is suggested that a PCE of >14% is realistic for tandem solar cells based on these commercially available donor materials. Along with the demonstration of novel intermediate layers we believe that this systematic study provides valuable insight for those attempting to realize the high efficiency potential of tandem architectures.
Energy and Environmental Science, 2013, Vol 6, Issue 12, p. 3407-3413