Study On Optical And Electrochemical Properties Of Carbon Materials

In recent years,with the in-depth research on carbon materials by major scientific research institutions and universities,the research of carbon materials has become more and more in-depth,and it has been found that carbon materials have played an irreplaceable role in cutting-edge basic research or in the development of strategic emerging industries.At present,the research on fluorescent carbon dots mainly includes non-metallic element doping.The surface state of fluorescent carbon dots is changed by doping non-metallic elements,which improving the fluorescent effect of carbon dots.The study is found that N doping can increase the fluorescence QY of carbon dots;S doping can significantly change the emission wavelength of PL,leading to red shift;and F doping can increase the fluorescence intensity of carbon dots.Most of the current researches on fluorescent carbon dots focus on blue and green carbon dots.Research on red carbon dots is relatively rare.The preparation of red carbon dots is more complicated,which also severely restricts the full-spectrum fluorescent carbon of visible light.In addition,carbon materials can also be used as anode materials for LIBs.Because of carbon materials have good electrical conductivity,good theoretical specific capacity and low cost,the study of carbon anode materials for LIBs also has important practical value.The main research contents of this thesis are as follows:1.Using anhydrous citric acid as a carbon source,fluorescent carbon dots were prepared by hydrothermal method.The influence of the concentration of raw materials,filling degree of hydrothermal solution,and holding time on the preparation of carbon dots was explored.Characterize and explore the best preparation plan.2.Using anhydrous citric acid as a carbon source,doping and modifying it with non-metallic elements,it is found that the incorporation of N element greatly increases the fluorescence intensity of the carbon dots,and then the optimal N doping concentration is explored.3.Using anhydrous glucose as the carbon source,it is found that after changing the carbon source,the emission peak has a large-scale red shift phenomenon.And through the N doping modification,the red light carbon dots are successfully prepared.Thereby successfully preparing the visible light full-spectrum fluorescent carbon point.4.Using anhydrous glucose as the carbon source,the precursor of the LIBs electrode carbon anode material was prepared by hydrothermal carbonization,and then subjected to high-temperature carbonization to prepare the lithium battery negative electrode carbon material required for the experiment.In this course,we mainly explored the influence of different high-temperature carbonization temperatures on the electrochemical performance of LIBs carbon anode materials.