Study On Nano-sized Yttrium Aluminum Garnet Prepared In Integrated High-gravity And Microwave Technology

Nano YAG is a kind of important functional material,widely used in light,laser,ceramics due to their good chemical stability,thermal performance,strong mechanical performance,good optical properties etc.Among of existing preparation nanometer YAG powder in the method,solid-state reaction route is the production mode for the preparation of commercialized phosphors.However,this method has some unavoidable shortcoming and disadvantages,such as uniformity sent,agglomeration seriously,impurities attribute to grinding process and so on.Sol-gel process and Gel combustion can get the tiny particles at the low temperature,and morphology controllable,but it has limited its mass production,and the prices of the use of raw materials are expensive.Some organic raw materials can cause pollution.Spray pyrolysis method have traditional liquid phase method and solid phase method advantages at the same time.However,spray pyrolysis method is easy to form the hollow particles,the particles' broken pieces will produce debris.Compared with these methods,co-precipitation is one of the most application prospects because of the cheap raw materials,a simple synthesis and easiness to carrying out.Nanosize pure phase YAG powders have been synthesized by the co-precipitation at a low temperature.However,the average particle size and the dispersed is not ideal.In order to solve defects of preparation YAG powder by the precipitation,such as easy reunions,particle size distribution inequality,this paper using rotating bed with helix channels(RBHC)produces the gravity to great strengthen the reaction of mass transfer process and micromixing,make a nuclear size uniform form,reduce the reunion,so as to control the size of the particle size and uniformity.At the same,water-alcohol as solvent which regulate the precipitation agent dielectric constant to control the size and the reunion of particles.In sintering process,using the microwave heating,which have characteristics of heating time even short,reduce the possibility of second crystallization,and can prepare fine size products which we need by control precursor body.Reseaching the preparation process conditions on the influence of the products,using FT-IR,TG-DSC,XRD,SEM,TEM,ect.methods to study the characterization of products,the result shows that the selection of revolving speed of RHBC is 800-1000 rpm,to Al(NO3)3·9H2O as aluminum source,NH4HCO3 and NH3H2O for mixed the precipitation agent,alcohol volume fraction is 30%alcohol-water as precipitation agent solvent,Pure phase YAG powders with average size of 35 nm can be synthesized by reverse strike(RS)process in the high-gravity environment generated by RBHC when calcined at 1000? for 2 h.Moreover,the products are well-crystallized and well-dispersed.On the basis of the preparation of nanometer YAG powder,this paper using high gravity technology and microwave technology integration prepare YAG:Ce phosphor,and study its luminous property.Investigating the different Ce doping source and the different of doping amount influence on the performance of YAG:Ce phosphors,using FT-IR,TG-DSC,FT-IR,TG-DSC XRD,SEM,TEM,EL,etc.methods to study the characterization of products,the result showes that the high quality nano YAG:Ce phosphor can be prepared by the super gravity technology and microwave technology integration route,and Ce(NO3)3 6 H2O as cerium source,Ce doping volume is 0.06.