A new role of TiO2 nanoparticles as dark quenching inhibitors in poly(9,9'-di-n-octylfluorenyl-2.7-diyl) (PFO)/Fluorol 7GA blends prepared using solution blending method was investigated. The results showed simultaneous reduction in PFO and increment in Fluorol 7GA emissions thus confirms efficient energy transfer between these materials. Once Fluorol 7GA content exceeded 0.5 wt.%, the Fluorol 7GA emission decreased rather than increased due to dark quencher formation. The incorporation of TiO2 in the blends successfully inhibited the formation of dark quenchers. The maximum brightness and luminance efficiency were obtained at TiO2 contents of 25 and 15 wt.%, respectively. (C) 2013 Elsevier B.V. All rights reserved.