Regulation Of The Fluorescence Properties Of Carbon Quantum Dots And Its Application

Carbon quantum dot(CDs)is a new type of carbon nanomaterials,which has attracted much attention in recent years.Due to its excellent fluorescence properties,it has been applied in many fields such as biological imaging,analytical detection and catalysis.However,it is difficult to develop tunable multicolor luminescence CDs,which limits the application of CDs in biological imaging,anti-counterfeiting and photoelectric devices.Besides,the aggregation-caused quenching effect(ACQ)of CDs is also another limiting factor its application.Therefore,it is very important to adjust and control CDs fluorescence properties to solve this problem.Based on fluorescence properties of CDs,two kinds CDs with special fluorescence properties have been successfully prepared,and CDs fluorescence properties have been regulated.The main contents are as follows:(1)CDs with solid-state fluorescence properties were successfully prepared by microwave method,and the colors of CDs solid-state fluorescence were controlled by changing reaction time.The proposed CDs luminescence mechanism is investigated.These experiments show that the production of solid-state fluorescence is related to the doping of boron element,and the change of fluorescence color can be attributed to the quantum size effect.In the absence of any other substrate materials,CDs have been successfully applied to the fabrication of light emitting diodes.(2)White light emitting CDs were prepared by one step hydrothermal method.The CDs has no solid-state fluorescence because of ACQ.By dispersed in the solid matrix,the liquid to-solid-state fluorescence of CDs can be controlled.The white light characteristic of CDs was successfully applied to light emitting diodes.In addition,it is found that the CDs has the ability to precipitate heavy metal ions and can be used as adsorbents,and the adsorption properties of CDs are also studied.