In-Situ Switching from Barrier-Limited to Ohmic Anodes for Efficient Organic Optoelectronics (pages 3051–3058)
Zhi-Kuang Tan, Yana Vaynzof, Dan Credgington, Cheng Li, Mike T. L. Casford, Alessandro Sepe, Sven Huettner, Mark Nikolka, Fabian Paulus, Le Yang, Henning Sirringhaus, Neil C. Greenham and Richard H. Friend
Article first published online: 12 FEB 2014 | DOI: 10.1002/adfm.201303426
A polar non-solvent treatment switches anode surfaces from barrier-limited hole injection/extraction to ohmic behavior. This is caused by the removal of polar hydroxyl groups, increasing the anode work function. In photovoltaic devices, a two-fold enhancement in hole extraction raises the fill-factor and open-circuit voltage, leading to high power-conversion efficiency. In light-emitting diodes, hole injection and luminance intensity increase by 3 orders of magnitude.