Luminous Butterflies: Efficient Exciton Harvesting by Benzophenone Derivatives for Full-Color Delayed Fluorescence OLEDs

Butterfly-shaped luminescent benzophenone derivatives with small energy gaps between their singlet and triplet excited states are used to achieve efficient full-color delayed fluorescence. Organic light-emitting diodes (OLEDs) with these benzophenone derivatives doped in the emissive layer can generate electroluminescence ranging from blue to orange-red and white, with maximum external quantum efficiencies of up to 14.3%. Triplet excitons are efficiently harvested through delayed fluorescence channels.