Rationally Designed Matrix‐Free Carbon Dots with Wavelength‐Tunable Room‐Temperature Phosphorescence

Abstract

We report the rational design of the matrix-free carbon dots (C-dots) with long wavelength and wavelengthtunable room-temperature phosphorescence (RTP). Taking advantage of microwave-assisted heating treatment, three RTP C-dots in boric acid (BA) composites are synthesized by using diethylenetriaminepentakis (methylphosphonic acid) as a multiple-sites crosslink agent, a moderately acid catalyst and P source; phenylenediamines (either o-PD, m-PD, or p-PD, respectively) as building block while BA as a carbon-ization-retardant matrix. After the water-soluble BA matrix is removed by dialysis, three matrix-free C-dots are obtained with RTP emission at 540, 550 and 570 nm under an excitation wavelength of 365 nm. Alterations of RTP emission of three matrix-free C-dots are ascribed to the difference in their particle size and band gap from n-π* transition. Furthermore, the application of three matrix-free C-dots are successfully performed in information encryption and decryption.

Multicolor Afterglow from Carbon Dots: Preparation and Mechanism

“…Furthermore, due to the differences in molecular structures, isomers have been widely used to prepare multicolor fluorescent CDs. Inspired by this concept, Qi et al [109] prepared CDs-based long afterglow materials with yellow, yellow-green, and yellow-white afterglow by using microwave assisted heating method. The results show that the modulation of particle size, surface state and 𝜋-𝜋 interactions within CDs can be tuned by changing three PD precursors.…”