溶胶-凝胶法在3D-SiC陶瓷表面制备纳米MgO薄膜

Preparation of MgO Nanofilm on Surface of 3D-SiC by Sol-Gel Method

以Mg(NO3)2.6H2O为原料,无水乙醇为溶剂,胶棉液为表面活性剂,利用溶胶-凝胶法制备了MgO溶胶,并利用浸渍提拉法在三维网络-碳化硅(3D-SiC)陶瓷骨架表面涂覆MgO溶胶,经煅烧制得纳米MgO薄膜.利用X射线衍射仪(XRD)和扫描电子显微镜(SEM)分析了薄膜的物相和显微结构.结果表明,利用浸渍提拉法在HF溶液浸蚀后的3D-SiC骨架表面涂覆质量比m(Mg(NO3)2.6H2O)∶m(胶棉液)=1.0的MgO溶胶后,在80℃干燥10 min,再升至480℃干燥10 min,最后800℃煅烧1 h,可制备出致密平整,厚度为0.8～1.0μm的纳米MgO薄膜.薄膜与骨架结合良好,MgO晶粒平均粒径约为500 nm.

With Mg（NO3）2·6H2O,anhydrous ethanol and collodion emulsion used as starting materials,solvent and surfactant,respectively,the MgO sol was prepared by sol-gel method.Then the MgO sol was coated on the surface of the ceramic skeleton of 3D-SiC by dip-coating process to get MgO nanofilm after roasting.The phase composition and microstructure of the nanofilm were investigated via XRD and SEM.The results showed that the smooth and compact MgO nanofilm whose thickness ranges from 0.8 to 1.0 μm can be deposited on the surface of 3D-SiC as substrate the way the substrate should be eroded in HF solution for 30 min to make sure that the coated MgO sol has the mass ratio of Mg（NO3）2·6H2O to collodion emulsion is equal to 1.0,then it is dried at 80 ℃ for 10min and,later on,at 480 ℃ for 10min and roasted at 800 ℃ for 1 hr.The MgO nanofilm is bonded well to the substrate,and its average particle size is about 500 nm.