Facile access to B-doped solid-state fluorescent carbon dots toward light emitting devices and cell imaging agents

A green and facile hydrothermal approach for carbonizing boric acid and ethylenediamine into B-doped carbon dots (CDs) has been proposed, providing a new method to synthesize functional carbon dots on a large scale. The obtained B-doped CDs exhibit favorable aqueous solubility and strong fluorescence in both aqueous and solid states. Especially, the unique solid-state fluorescence properties of the B-doped CDs inspire new thoughts for other applications, accordingly a yellowish-green light emitting diode with the as-obtained CDs as light converters is demonstrated. Meanwhile, the as-prepared CDs also display intensely low toxicity and excellent multicolour fluorescence imaging ability in live cells.