Color integration in biomass-derived carbon dots to realize one-step white light

In this work, the extract of mango leaf was chosen as a green raw material, and ethylenediamine (EDA) as a supporting material for a controllable one-step reaction to realizing white light. During the reaction, EDA could balance the precursor consumption, and participated in the formation of the carbon dots (CDs). The final integrated emitting color of the materials could be adjusted to white light with a one-step hydrothermal treatment. The composite solution was directly coated on a commercial 365 nm light-emitting diode (LED) chip without a polymer matrix and showed a stable white light with CIE coordinates of (0.326, 0.328). This work developed an interesting method for tuning the reaction process in a complex system and provided a simple way of realizing an integrated white light with a single wavelength excitation.