Chemical doping is an important strategy to alter the charge-transport properties of both molecular and polymeric organic semiconductors that find widespread application in organic electronic devices. We report on the use of a new class of Co(III) complexes as p-type dopants for triarylamine-based hole conductors such as spiro-MeOTAD and their application in solid-state dye-sensitized solar cells (ssDSCs). We show that the proposed compounds fulfill the requirements for this application and that the discussed strategy is promising for tuning the conductivity of spiro-MeOTAD in ssDSCs, without having to rely on the commonly employed photo-doping. By using a recently developed high molar extinction coefficient organic D-π-A sensitizer and p-doped spiro-MeOTAD as hole conductor, we achieved a record power conversion efficiency of 7.2%, measured under standard solar conditions (AM1.5G, 100 mW cm -2). We expect these promising new dopants to find widespread applications in organic electronics in general and photovoltaics in particular. © 2011 American Chemical Society.
Bibliographical noteKAUST Repository Item: Exported on 2020-10-01
Acknowledged KAUST grant number(s): KUS-C1-015- 21
Acknowledgements: The authors thank Dr. Hoi Nok Tsao for help with conductivity measurements and Prof. Peng Wang for providing the C220 sensitizer. This publication is partially based on work supported by the Center for Advanced Molecular Photovoltaics (Award No KUS-C1-015- 21), made by King Abdullah University of Science and Technology (KAUST). M.K.N. thanks the WCU (the Ministry of Education and Science) Program (No. R31-2008-000-10035-0).
This publication acknowledges KAUST support, but has no KAUST affiliated authors.