Ionic Liquid-assisted Synthesis Of The Carbon Nanomaterial With Low Dimension

In recent years,the carbon nanomaterial with low dimension was found gradually along with the developed of science and technology.As the behalf of the carbon nanomaterial with low dimension,zero-dimensional carbon dots and two-dimensional grapheme has gotten much attention and great progress in many aspects such as structure,pattern,property,synthesis,application area.But the issue of common preparation(the oxidation of graphite with strong oxidizer,the exfoliation of graphite)such as the complex synthetic procedures and harsh experimental condition and separation processes are currently serious restricting the application field of them.Meanwhile the study of low-dimensional carbon nanomaterial with different doping elements like N?S?B has obtained great progress,and the corresponding aspects has been explored like character ?framework ?use and so on.On the basis of the research which is referred to above,a new route is pressing needed to synthesis carbon dots and large flake of grapheme-like materials,meanwhile this approach has very simple synthetic procedures and easy film processing performance in optoelectronic applications.This paper also reported a novel and easy method to produce p-type,n-type grapheme-like carbon sheet and composite material with p-n heterojunction,at the same time it is studied to compare the photoelectric conversion property in these types grapheme-like carbon sheet.The paper is consisted of the following three parts:(1)The thermal decomposition polymerization method has been applied to synthesis the carbon nanomaterial with low-dimension,with ionic liquid(1-butyl 3-methyl imidazolium bromide)as solvent and L-cysteine as raw material.Then the way to produce zero-dimensional carbon dots and two-dimensional carbon sheets is available through some means such as transmission electron microscope,atomic force microscope,X-ray photoelectron spectroscopy,X-ray diffractometer,ultraviolet,fluorescence to characteristic the structure,pattern and optical properties of the outcome with some isolation and purification.The study of reaction mechanisms and electrochemical properties of the N,S doped carbon nanomaterial with low-dimension was carried on by changing the reaction time.The study reveals that the ionic liquid(IL)plays crucial roles in optimization of the synthetic operation process,improvement of the sample's dispersibility in common solvents and simplifying the processes for fabrication of photovoltaic device for the IL blended products(noted as IL+CD/CS).Meanwhile,the synergistic effects of the CD and CS for electronic charge generation and transport on their enhanced photocurrent response activity and photoelectric conversion efficiency are also explored.It is anticipated that the work may open a new window to facilely prepare novel carbon nanostructures for a wild range of application.(2)The exploration is also aimed to learn the production of three types(undoped,B-doped and N-doped)of carbon nanomaterial with low-dimension,using the thermal decomposition polymerization with ionic liquid as solvent and citric acid,boric acid,ethylene diamine tetraacetic acid(EDTA)as reactants.It is reported that B-doped carbon sheets is p-type semiconductor and N-doped carbon sheets is n-type semiconductor through Mott Schottky and cyclic voltammetry.Meanwhile,the study reveals that the photocurrent value of the composite material with p-n heterojunction which is gained by electrolytic deposition is evident higher than that of three types carbon sheets(undoped,B-doped and N-doped)in electrochemical activity.(3)It is reported that the high blue-fluorescent soft material is gotten by small organic molecules at mild temperature with deionized water as solvent.A new blue-fluorescent soft material with high quantum yield(89.6%)and eutectic feature prepared by simple heat treatment of citric acid and cysteine aqueous mixtures blew 100? in air was reported.The as-prepared fluorescent material has the features of facile preparation,low cost,scalable production and easy to process,making it suitable for applications like fluorescent labeling and light-emitting devices.