Tailored exciton diffusion in organic photovoltaic cells for enhanced power conversion efficiency

Photoconversion in organic photovoltaic cells, which relies on charge generation at donor/acceptor interfaces, is limited by short exciton-diffusion-lengths. Diluting an electron donor into a wide-energy-gap host material has now led to an ~50% increase in exciton diffusion length and enhanced power conversion efficiencies in planar heterojunction cells compared with optimized devices with an undiluted donor layer.