Study On The Composition,Adjustment And Room Temperature Phosphorescence Properties Of Carbon Dots/Polymer Matrix

In recent years,carbon dots(CDs)have been widely studied by researchers because of their excellent optical properties,good biocompatibility,easy preparation and modification.At present,most of the researches of carbon dots are focused on their fluorescence properties.The afterglow properties of carbon dots have not been fully explored.Most of the traditional room temperature phosphorescent materials are inorganic salts and metal complexes containing rare earth metals.Although the room temperature phosphorescence emission of these materials has a long average life and quantum yield,the synthesis process is often complex and expensive.At the same time,it often contains rare precious metals,which is not conducive to biological applications.As a kind of pure organic nanomaterial,carbon dots can overcome the shortcomings of traditional room temperature phosphorescent materials,and make it a good alternative material for new room temperature phosphorescent materials.In recent years,carbon dots based room temperature phosphorescent materials have made great breakthroughs,but there are still many problems to be solved.For example,it is necessary to synthesize more highly controllable carbon dots.The transmitters of carbon dots based room temperature phosphorescent materials are controversial.There is a lack of systematic control of their phosphorescent properties,and the research on the interaction between carbon dots and matrix is not clear enough.Based on these problems,we have made the following efforts.By adjusting the carbon dots and matrix respectively,the interaction between the carbon dots and matrix is further regulated,and the room temperature phosphorescence property is finely tuned,and the room temperature phosphorescence property is applied in the field of time-resolved anti-counterfeiting.The main contents of this paper are as follows:(1)The room temperature phosphorescence emission of polyaniline carbon dots was realized for the first time,and two new substrates suitable for carbon dots based room temperature phosphorescence materials were explored.Polyaniline carbon dots were prepared by a simple room temperature chemical wet process.Based on the strong hydrogen bond effect of polyaniline carbon dots,two hydrophilic polymers,polyacrylamide and polyacrylic acid,were selected as the matrix to realize the room temperature phosphorescence emission of polyaniline quantum dots.The longest room temperature phosphorescence lifetime reached 652 ms.(2)By adjusting the carbon cots and the matrix,the phosphorescence property of the phosphorescent material was finely tuned,and the time-resolved anti-counterfeiting application of room temperature phosphorescence was realized.Thanks to the simple and easy synthesis of polyaniline by wet chemical method at room temperature.A series of polyaniline carbon dots with similar properties were synthesized by introducing different functional groups into the monomer and adjusting the structure of the monomer.From the point of view of carbon dots and matrix,the influence of the interaction between them on the phosphorescence was studied systematically.The green phosphorescence emission with an average lifetime of 182 ms to 652 ms was obtained.Using this property,the time-resolved room temperature phosphorescence anti-counterfeiting application has been realized.(3)The effects of hydrogen bonding and heavy atom effect on room temperature phosphorescence were investigated.Halogen doped carbon dots based room temperature phosphorescent materials were obtained by introducing fluorine atom and chlorine atom into polyaniline carbon dots monomer respectively.The effects of strong hydrogen bonding caused by fluorine atoms and heavy atom effects caused by chlorine atoms on the phosphorescence properties of carbon dots based room temperature phosphorescent materials were explored.