"Our hope is that this will be a game changer for organic photovoltaics by simplifying the process for fabricating polymer-based solar cells," said Bernard Kippelen from Georgia Tech. "We believe this technique is likely to impact many other device platforms in areas such as organic printed electronics, sensors, photodetectors and light-emitting diodes."
The technique consists of immersing thin films of organic semiconductors and their blends in polyoxometalate solutions in nitromethane for a brief time at room temperature. The diffusion of the dopant molecules into the films during immersion leads to efficient p-type electrical doping over a limited depth of 10 to 20nm from the surface of the film.
The p-doped regions are said to show increased electrical conductivity and high work function. When applied to polymer solar cells, the doping method provided efficient hole collection.
This method provides an alternative to air sensitive molybdenum oxide layers that are generally processed using expensive vacuum equipment.
"Being able to process solar cells entirely at room temperature using this simple solution-based technique could pave the way for a scalable and vacuum-free method of device fabrication, while significantly reducing the time and cost associated with it," said PhD researcher Vladimir Kolesov.
According to PhD student, Fleipe Larrain, it could one day enable people to power themselves and be independent of the grid.
