Dynamic Room Temperature Phosphorescence of Silane‐Functionalized Carbon Dots Confining within Silica for Anti‐Counterfeiting Applications

Abstract

AbstractRoom temperature phosphorescent (RTP) materials with long‐lived, excitation‐dependent, and time‐dependent phosphorescence are highly desirable but very hard to achieve. Herein, this work reports a rational strategy of multiple wavelength excitation and time‐dependent dynamic RTP color by confining silane‐functionalized carbon dots (CDs) in a silica matrix (Si‐CDs@SiO2). The Si‐CDs@SiO2 possesses unique green‐light‐excitation and a change in phosphorescence color from yellow to green. A slow‐decaying phosphorescence at 500 nm with a lifetime of 1.28 s and a fast‐decaying phosphorescence at 580 nm with a lifetime of 0.90 s are observed under 365 nm of irradiation, which originated from multiple surface triplet states of the Si‐CDs@SiO2. Given the unique dynamic RTP properties, the Si‐CDs@SiO2 are demonstrated for applications in fingerprint recognition and multidimensional dynamic information encryption. These findings will open an avenue to explore dynamic phosphorescent materials and significantly broaden their applications.