Study On The Preparation And Properties Of MXene/TMOs

Transition metal oxide（TMO）catalysts have been widely used as combustion catalysts in solid propellants,but due to their small size and high surface energy,TMO catalysts are prone to agglomeration,resulting in a decrease in catalytic activity.Based on the special two-dimensional structure of MXenes and the advantages of high surface area,hydrophilicity,and good electrical conductivity,the transition metal oxide nanoparticles were loaded onto the surface of MXenes to construct MXene/TMOs composites and achieve uniform dispersion of the nanometallic oxide particles.The catalytic effect of the MXene/TMOs composites on the thermal decomposition of ammonium perchlorate was investigated,and the corresponding catalytic mechanism was discussed as follows.Firstly,The MXene/NiCo₂O₄ composite was prepared by calcination method.The effect of calcination temperature on the preparation of composite materials was studied.The results showed that the optimal calcination temperature for MXene/NiCo₂O₄ composites prepared by calcination method was 300°C.At this temperature,NiCo₂O₄ in the composites was flower-like and successfully dispersed on the surface of MXene materials.Study the effect of mass ratio on the catalytic effect of MXene/NiCo₂O₄ composite material.The catalytic effect of MXene/NiCo₂O₄ composite material increases with the increase of NiCo₂O₄ content in the composite material.Among them,MXene/50%NiCo₂O₄ nanocomposites could lower the AP pyrolysis temperature by 119.9°C.Secondly,after peeling off the multilayer MXene into a single layer of d-MXene,the d-MXene/Zn O nanocomposite was prepared by hydrothermal method,and the influence of hydrothermal time and mass ratio on the morphology and structure of the d-MXene/Zn O composite was studied.It shows that the optimal hydrothermal time is 3 h,and under this time,Zn O nanoparticles can be uniformly dispersed on the surface of d-MXene,and the structure of d-MXene is not damaged.The effect of hydrothermal time and mass ratio on the catalytic effect of d-MXene/Zn O composites was studied.The catalytic effect of d-MXene/Zn O samples prepared when the hydrothermal time was 3 h was better than that of samples at other times,and the catalytic effect of the d-MXene/Zn O composite material increases with the increase of the Zn O content in the composite material.Among them,the d-MXene/50%Zn O composite material can reduce the AP high temperature decomposition peak by 132°C.Finally,using glucose as a carbon source to hydrothermally carbonize the surface of MXene to prepare carbon-coated MXene@C material,and then further use the redox reaction between the carbon layer and potassium permanganate to grow Mn O₂ nanoparticles in situ,and successfully prepare Mn O₂/MXene@C composite materials.Mn O₂ nanoparticles are uniformly loaded on the surface of MXene@C,and during the preparation process,MXene has not been oxidized,indicating that the coating of carbon materials can effectively avoid the oxidation of MXene materials.Study the effect of mass ratio on the catalytic effect of Mn O₂/MXene@C composite material.The catalytic effect of Mn O₂/MXene@C composites on AP was gradually enhanced with the increase of Mn O₂ content in the composites,and the pyrolysis peak of AP was advanced by 128.8 ^oC with the addition of 50%Mn O₂/MXene@C.