A micro-wave strategy for synthesizing room temperature phosphorescent materials

Abstract

Room temperature phosphorescent (RTP) materials have a variety of applications ranging from bio-imaging, optoelectronic devices to information security protection. However, the preparation procedures for these materials are always tedious and time-consuming. Here, we report a micro-wave approach to prepare RTP carbon dots (CDs) in only 8 min. The micro-wave promoted the carbon and boron bond formation using natural compounds glucose and boric acids. This result has been confirmed using TEM, FTIR, XPS and XRD measurements. The C-B hetero atomized material presented a long afterglow property. With the irradiation with UV light, we observed an eight-second RTP by naked eyes after the lamp was turned off, and the phosphorescence lifetime was 487 ms. This excellent performance was mainly due to the formation of B-C bonds that promoted the intersystem crossings (ISC) and non-radiation transition of triplet states. Moreover, the glass state of the materials also helped to stabilize the triplet states of B-CDs and made its non-irradiation inactivated, which resulted in the characteristics of yellow green RTP. These results have demonstrated that micro-wave is a convenient and effective strategy to make hetero atomized RTP material, providing new possibilities for their industrial productions.