The Current Progress and Challenges of Carbonized Polymer Dot-Based Room-Temperature Phosphorescent Materials

Carbonized polymer dots(CPDs)as one type of carbon dots have attracted widespread attention in recent years.The proposal of the“shell–core”structure of CPDs leads to further thinking about the association between their special structures and luminescent properties.In recent years,great progress has been made in the field of CPD-based room-temperature phosphorescent materials.This review pays particular attention to how the special“core–shell”structure of CPDs influences the activation of roomtemperature phosphorescence(RTP).The strategies and vital factors to activate RTP for CPD-based materials in both solid state and water were reviewed in detail to elaborate on the effect of the special structure on RTP generation.Furthermore,some perspectives on the current challenges were also provided to guide the further development of CPD-based room-temperature phosphorescent materials.

Confined-domain crosslink-enhanced emission effect in carbonized polymer dots

Revealing the photoluminescence(PL)origin and mechanism is a most vital but challenging topic of carbon dots.Herein,confined-domain crosslink-enhanced emission(CEE)effect was first studied by a well-designed model system of carbonized polymer dots(CPDs),serving as an important supplement to CEE in the aspect of spatial interactions.The“addition-condensation polymerization”strategy was adopted to construct CPDs with substituents exerting different degrees of steric hindrance.The effect of confined-domain CEE on the structure and luminescence properties of CPDs have been systematically investigated by combining characterizations and theoretical calculations.Such tunable spatial interactions dominated the coupling strength of the luminophores in one particle,and eventually resulted in the modulated PL properties of CPDs.These findings provide insights into the structural advantages and the PL mechanism of CPDs,which are of general significance to the further development of CPDs with tailored properties.

Achieving blue water-dispersed room-temperature phosphorescence of carbonized polymer dots through nano-compositing with mesoporous silica

Stabilizing triplet excited states is important for room temperature phosphorescence(RTP)materials to achieve multifunctional applications in humid environment.However,due to the lack of preparation strategies,the realization of RTP materials in water still faces challenges.Herein,a new design strategy was presented to achieve RTP in water by confining carbonized polymer dots(CPDs)in amino functional mesoporous silica(MSNs-NH_(2)).The as-prepared MSNs-CPDs aqueous dispersion exhibited blue afterglow,lasting more than 3 s to naked eyes.The triplet excited states were protected from non-radiative deactivation by the double-confinement effect including covalent bonding fixation and mesoporous structure confinement.The MSNs-CPDs inherited the structure of MSNs-NH_(2),so the stability of morphology and properties were superior to CPDs and even most of silica-based CPDs RTP materials.A water-related encryption technique demonstrated the promising application of MSNs-CPDs as smart materials in the field of information security.Besides,the possibility of potential application in ion detection was also explored.