Preparation And Modification Of MXene Based On New Deep Eutectic Solvent

Due to the properties of two-dimensional materials in mechanics,chemistry,magnetism,and optics,the exploration of these materials in the fields of organic electronics,electronic components,electrochemical energy storage,sensing and catalysis are attracting more and more researchers’interest.However,MXene needs to go through the etching and exfoliating process of the precursor material from preparation to use.During this process,the reaction system has high risk and harsh reaction conditions that need to be solved urgently.The deep eutectic solvent（DES）,as a conductive liquid between general molecular solvents and ionic solvents,has high viscosity,non-volatility,and non-toxicity.Among them,a new eutectic solvent formed by a metal salt chloride and a small molecule hydrogen bond donor as a room temperature molten salt can provide a reaction environment for the etching of the MAX phase precursor.Based on this,the research ideas of this paper are as follows:（1）A new deep eutectic solvent in the etching preparation of MAX is developed.In this paper,the Al layer of MXene is selectively etched by virtue of the oxidative properties of free ion clusters in a novel deep eutectic solvent formed by metal salt chloride and ethylene glycol.By selecting different metal salts and ethylene glycol to prepare deep eutectic solvents with different molar ratios,the conductivity,viscosity,phase transition and electrochemical laws were compared,and the reaction conditions suitable for redox were explored.In the subsequent etching experiments,the temperature of the reaction system,the reaction time and the feeding amount of the MAX phase of the precursor material were compared and discussed respectively.Experiments show that at a molar ratio of 1:10 of ferric chloride and ethylene glycol,the DES can etch the Ti₃AlC₂-MAX phase at 140℃for 12 h.（2）Fabrication of MXene/DES paper-based temperature sensor.In this paper,the photothermal conversion properties of MXene and the temperature-dependent properties of eutectic solvent conductivity are used to prepare MXene/DES conductive ink,and the material is screen-printed to prepare flexible sensors.By blending the MXene nanosheets prepared by HF etching with a novel deep eutectic solvent,a series of conductive inks with photothermal conversion ability were obtained,and temperature sensors were prepared using different flexible materials as substrates through processes such as screen printing.In the experiment,the effects of the amount of MXene powder added and the type of deep eutectic solvent on printing quality,temperature sensing and stability were discussed.The experimental results show that the new eutectic solvent formed by ferric chloride and ethylene glycol in a molar ratio of 1:4 can be blended with MXene powder in a mass ratio of 1:1 to obtain ink,and the paper obtained by screen printing The temperature sensor has high sensitivity and stability,and has certain application value.