OPV modules offer record efficiencies

The first is a fullerene-free OPV module with an area of just 160cm² and a conversion efficiency of 5%, and the second is a semi-transparent OPV module with an efficiency of 4.5%. imec says the successful upscaling represents a significant step towards realising commercial organic photovoltaics. The fullerene-free module was created by thermally evaporating small molecules in different active layers. The process has been shown to improve device stability, while at the same time opening up possibilities for further device engineering. In tests, the module achieved efficiencies of more than 5% in an opaque configuration on a glass substrate. Moreover, a performance of 8.4% in a single cell with 1cm² active area was achieved under solar spectrum illumination – the highest ever achieved with a non-fullerene acceptor. Under indoor light exposure, efficiencies were as high as 24%.