Visible-light-excited high efficiency multicolor room temperature phosphorescence of carbon dots in boric acid matrix

Visible light is safer for health and deeper penetrable than ultraviolet light, yet the development of room temperature afterglow (RTA) materials with visible-light-excitation remains an enormous challenge. A universal approach to acquire the activation of color-tunable carbon dots (CDs)-based RTA composites (CDs/BA) with excitation-dependent feature under visible light excitation with the highest quantum efficiency up to 54.27 % and long lifetime of 530 ms, surpassing most of nonmetallic afterglow materials under excitation of Vis-light. Meanwhile, CDs/BA exhibit color-tunable RTA properties from cyan to red at excitation of 420 nm via alteration in carbon source types. Benefiting by these excellent properties, CDs/BA composites were applied in advanced information security and anti-counterfeiting fields. Such a strategy provides an important way for the development of high-efficiency visible-light-excited RTA materials with color-tunability.