White light generation tuned by dual hybridization of nanocrystals and conjugated polymers

Dual hybridization of highly fluorescent conjugated polymers and highly luminescent nanocrystals (NCs) is developed and demonstrated in multiple combinations for controlled white light generation with high color rendering index (CRI) (>80) for the first time. The generated white light is tuned using layer-by-layer assembly of CdSe/ZnS core-shell NCs closely packed on polyfluorene, hybridized on near-UV emitting nitride-based light emitting diodes (LEDs). The design, synthesis, growth, fabrication and characterization of these hybrid inorganic–organic white LEDs are presented. The following experimental realizations are reported: (i) layer-by-layer hybridization of yellow NCs (λPL = 580 nm) and blue polyfluorene (λPL = 439 nm) with tristimulus coordinates of (x, y)= (0.31, 0.27), correlated color temperature of Tc = 6962 K and CRI of Ra = 53.4; (ii) layer-by-layer assembly of yellow and green NCs (λPL = 580 and 540 nm) and blue polyfluorene (λPL = 439 nm) with (x, y)= (0.23, 0.30), Tc = 14395 K and Ra = 65.7; and (iii) layer-by-layer 6 Author to whom any correspondence should be addressed. New Journal of Physics 9 (2007) 362 PII: S1367-2630(07)51460-6 1367-2630/07/010362+13$30.00 © IOP Publishing Ltd and Deutsche Physikalische Gesellschaft