Preparation And Application Of Nano-La₂O₃ And Nano-powders MoO₃

Nanotechnology is the late 20th century,developed a high-technology meters, preparation of nano-powders,nano-Materials have been applied to many fields,with the nano-powder,nano-materials in-depth tudy,21 century will be idelyusednano-technology era.Nano-powders,nano-materials are constituted by the Nano-particles,nano-particles by Its small size,large specific surface area,with a series of strange macro and micro effects.The existence of these effects Make nano-powder in a mechanical,optical,biological,chemical,electrical and many other unique physical,chemical and Quality,in many areas has been applied in various fields in the national economy will be more widely used.In this paper,the preparation of nano-materials and application of a systematic and in-depth study,the main research contents are as follows:1.Preparation of ultra-fine lanthanum oxide nanoparticles by ultrasonic-homogeneous precipitation methodUltra-fine lanthanum oxide nanoparticles were prepared with LaCl₃ (lanthanum) and CO(NH₂)₂(larbamide) as raw materials by hydrolyzation of urea, the products were characterized by XRD,SEM.DTA-TG,the XRD test result showed that the products were the six-party crystal and the average particle size(D50) was measurated in the instrument of laser-granularity-distributing.The author discussed the influences of the ratio of reactant concentration,ultrasonic time, calcining temparation and the concentration of Bromide Cetyltrimethylammonium (CTMAB) and(NH₄)₂SO₄ on the particle size of La₂O₃,effectually solved he influences of the cluster appeared in synthesizing,drying and calcing the precursor on La₂O₃ particle size.Results showed that ultra-fine La₂O₃ with particle size 15 nm were prepared on the appropriate condition of amount-of-substance concentration of CO(NH₂)₂,ultrasonic time,calcining temparation and the concentration of CTMAB and(NH₄)₂SO₄.2.Preparation of ammonium bicarbonate precipitated nano-La₂O₃Lanthanum chloride as raw materials to make precipitant ammonium bicarbonate to ethanol as dispersing agent,by chemical precipitation method to obtain precipitation of lanthanum precursor,obtained by the ignition of La₂O₃.Reaction time, reactant concentration,dispersing agent and calcination time on the original lanthanum oxide nano-particle size and the impact of agglomeration,the use of DTA-TG,TEM and XRD techniques for nano-characterization of lanthanum oxide powder,XRD showed that the precursor material calcined at 750℃under 2 hours, completely transformed into La₂O₃ oxide,and its smaller size,good dispersion is a hexagonal system,spherical particles,diameter of about 45nm;TEM showed that the reaction temperature and reaction concentration of La₂O₃ important factor in the original particle size,reaction temperature,with an average original particle size increases;reaction concentration,with an average original particle size decreased, reunion aggravated situation.By adding ethanol can effectively reduce the aggregation of La₂O₃ phenomenon.3.The Preparation of nano-powders MoO₃ by direct precipitationThis paper presents the preparation of nanometer-sized MoO₃ uhrafine powder by using(NH₄)₆Mo₇O₂₄·4H₂O and CH₃COOH precursor materials,to explore the effect of ultrasound-hexadecyl trimethyl ammonium bromide(CTAB),anhydrous ethanol solution of the impact of nano-oxide particle size,by changing the concentration of acetic acid,ammonium molybdate solution concentration or by adding a small amount of surfactant,different experimental conditions to study these reaction conditions on the morphology ofnano-ceramic oxide and three effects of particle size,to explore the possible formation mechanism,and Synthesis of nano-oxide to identify the best conditions,DTA-TG,SEM analysis and X-ray diffraction and other means of characterization of the synthesis of ultra-fine powder Product analysis was prepared by ultra-fine oxide particles of 30nm.