Fluorinated Carbon Nitride Enables High-Efficiency White Electroluminescence

Commercial white light-emitting diodes (WLEDs) are multicomponent-emitting devices, which suffer from photobiological risks and a poor color rendering index, making them unideal for indoor lighting applications. Single-component WLEDs with natural-like light are highly sought; however, they have rarely been reported. Here we demonstrate high-efficiency single-component WLEDs based on fluorinated carbon nitride. Fluorinated carbon nitride (FCN) was synthesized by using a simple one-step thermal polymerization method. Fluorination reduces vibrational electron relaxation of carbon nitride, boosting the photoluminescence quantum yield (PLQY) to 65%, constructs donor-acceptor structure, enhancing the electron and hole mobilities by 600 and 2.5 times, respectively, and increases high-energy electron transitions, enabling broadband white light emission. The optimized LED achieves white light electroluminescence with CIE coordinates of (0.28, 0.38) and a breakthrough external quantum efficiency of 3.2%. Our findings show the promising potential of low-cost carbon nitride-based monolithic emissive layers in WLEDs.