Project R-5795

FWO research project: Fullerene-free solution-processed bulk heterojunction organic photovoltaics (Research)

Organic solar cells (OSCs) form a class of thin-film photovoltaics offering attractive prospects for renewable energy production by providing low-cost, flexible and aesthetically appealing devices printable on large surfaces. In bulk heterojunction (BHJ) OSCs, electron donor and acceptor molecules are intimately mixed in the photoactive layer. The lab efficiency of said devices has steadily increased from 5 to 10%, close to the declared threshold for commercial applications, due to growing insights in the underlying physical phenomena, device optimization and chemical engineering of a myriad of donor materials. Till now, fullerenes turn out to be the superior electron acceptors. The promises of more generic and versatile low-cost non-fullerene acceptors have yet to be fulfilled. The extensive fundamental knowledge obtained over the years on conventional fullerene-based OSCs now offers a solid foundation for important leaps forward in the development of novel material combinations. In this project, we will investigate the crucial factors affording high performance in fullerene-free OSCs and design novel blends comprising of advanced donors and acceptors. By optimizing photon harvesting, blend morphology and charge separation/transport, while reducing recombination losses, the project aims at increased device efficiencies - up to the level of fullerene-based OSCs and ultimately beyond - and a substantial fundamental contribution to this exciting emerging research field.

01 January 2015 - 31 December 2018