Room temperature phosphorescence of carbon dots activated by layered double hydroxides for application in information encryption

Abstract

Counterfeiting has become increasingly serious in the information age. In terms of anti-counterfeiting, room temperature phosphorescence (RTP) materials have received great attention due to their long emission wavelength and lifetime, high signal–noise ratio, and rich excited state characteristics. However, due to the complex and strict synthesis conditions, low yield and poor stability of RTP materials, they cannot be widely used. Here, we employ layered double hydroxides (LDHs) with dual structural confinement as host rigid substrates to activate the RTP of carbon dots (CDs). Furthermore, based on the excellent oxygen barrier and plasticity of polyvinyl alcohol (PVA), three-component CDs-LDHs@PVA with enhanced RTP performance is prepared. Thus, owing to the simple fabrication process, low cost, and excellent RTP performance of the organic–inorganic composite materials, they could be the new generation of potential anti-counterfeiting and information encryption materials to protect confidential documents.