Luminescent Carbon Dots:Synthesis And Investigation Of Its Application On Optical Devices

In this paper,a series of carbon nanoparticles were synthesized by the hydrothermal method.The formation process was discussed through controlling different reaction temperature and different precursors in the synthesis of CDs.The effect of halogen doping and the low temperature testing environment on the fluorescence of carbon were discussed.The carbon dots powders were obtained after freeze-drying.The luminescent thin film was fabricated through mixing the CDs powders with polyurethane adhesive,then the light-emitting diode?LED?was fabricated when the luminescent thin film was packaged on a chip.Carbon dots and Eu³⁺complexes were entrapped into the silica-based ionogels by physical immersion,which hold a promising potential for the application of carbon nanoparticles in optoelectronic devices.?1?The reaction temperature was controlled to investigate the formation process of S-doped CDs?CDs-S?.Different low-molecule-weight organics were used as precursors,it reveals that the N and/or S atoms containing in the precursors are related to the formation and luminescence mechanism.?2?Herein,the carbon dots were synthesized by the hydrothermal method doped with F/N for the first time.The quantum yield of F/N doped carbon dots is higher than the original CDs without any dopant.The emission spectrum excited by360 nm was well fitted by double-Gaussian function which can be assigned to the quantum size effect and surface states.This can be further confirmed by the low temperature photoluminescence.Basically,the luminescent thin film was fabricated through mixing the F/N-CDs powders with polyurethane adhesive,then the LED was fabricated when the luminescent thin film was packaged on a 410 nm LED chip.The obtained white-LED provides a new potentiality for the applications of carbon nanoparticles in optoelectronic devices.?3?Herein,the carbon dots were synthesized by the hydrothermal method.The Eu³⁺?-diketonates complexes with the characteristic emission were selected as the lanthanite resources.Silica-based ionogels prepared by a sol-gel route,ionic liquids in the ionogels were extracted with acetonitrile and nanosized pores among ionogels were obtained.The carbon dots and Eu³⁺complexes were homogeneously entrapped in the ionogels without any devitrification by doping the ionic liquid solution in the silica network of the ionogels.The obtained Eu³⁺-doped ionogels-functionalized carbon dots monolith are transparent and uniform with promoted mechanical properties and stability.Carbon dots were confinded in the nanosized pores among ionogels,resulting a certain distance between the carbon dots as well as preventing them from aggregation,which contributed to a high photoluminescence.The monoliths emit bright white photoluminescence under UV excitation after various studies of the proportion for carbon dots and Eu³⁺complexes.Eu³⁺-doped ionogels-functionalized carbon dots monoliths provides a new potentiality for the applications of carbon nanoparticles in optoelectronic devices.