Research On Preparation And UV-Vis Near Infrared Relfection Properties Of Doped-NaZnPO₄Materials

NaZnPO₄（referred to as NZPO） and its doping materials were prepared by heat-treatingprecursor at400⁸00℃with Zn（NO₃）₂6H₂O（zinc sulfate）、H₃PO₄and anhydrous sodiumcarbonate etc as raw materials via direct precipitation. The effect of phosphorus-zinc moleratios, stirring speed, water bath temperature and time, heat-treatment temperature on crystalstructure, morphology, particle size and UV-vis and near infrared reflection of the productwere analysised by XRD、TG/DSC and SEM etc. Besides, the coating was prepared by thebest reflective material as filler, and the insulation performance were tested by homemadedevice.The experiment results show that:（1） The preparation of sodium zinc phosphate by thecondition of phosphorus zinc ratio at1.7, stirring speed of100r/min, water bath temperatureof70℃, water bath time of0.5h. The NaZnPO₄at heat-treatment temperature of600℃whichhas the highest average reflectivity of95.2%, much higher than that of TiO₂. The UVreflective properties of the product will decline apparently in the case of particles melting anduneven distribution of particle size, and the growth of crystal particles is good for improvingthe visible and near-infrared reflective properties.（2）1%of aluminum doped A1NZPO asdoping material in heat treatment temperature of600℃has the average reflectivity of96.51%,higher than that of NaZnPO₄.（3）La-doped and Eu-doped can improve the ultraviolet reflexperformance; Ce-doped can improve the near infrared reflection properties of the material.C_0.01L_0.05NZPO prepared at the heat-treatment temperature of400℃has the highest UVreflection of99.86%, which is up7.85%more than that of NZPO; C_0.01L_0.05E_0.05NZPO at700℃has the highest visible reflection of99.22%, which is up2.01%more than that ofNZPO, and it has the best the near infrared reflection of97.81%, which is up1.39%morethan that of NZPO.（4）The coating was prepared by50%acrylic emulsion as the film,50%C_0.01L_0.05E_0.05NZPO as reflective material, which had smooth surface, strong coherencestrength. The test of heat insulation of the material shows that the air temperature of the plateback can reduce by10.7℃, comparing with TiO₂of7.5℃and ZnO of7.9℃.Comprehensive analysis shows that NaZnPO₄and its doping materials have goodreflective properties in UV-vis near-infrared wavelengths. By using it in coating packing would have a good thermal insulation effect. The research of UV-vis near infrared reflectiveproperties of doping materials has important significance to the study of reflecting materials,heat insulation materials,etc... The research and application has great guidance and benefits toeconomy, society and environment.