以3-氨丙基三乙氧基硅烷(3-APTES)为表面修饰剂,利用乙氧基与SnO2表面羟基之间的化学反应,将SiO2化学接枝于SnO2表面,以阻止SnO2晶粒热生长.采用SEM、TEM、FT-IR、XRD和EDS等技术对改性后纳米SnO2进行结构表征.结果表明,SiO2通过Sn—O—Si化学键与SnO2相连接,SiO2被高度分散于SnO2表面.经1000℃高温煅烧后,SnO2平均粒径改性前后分别为95和10nm.SiO2作为第二相,阻碍了晶界的移动,增加了晶粒生长活化能,从而有效地限制了晶粒高温生长,提高了纳米SnO2的热稳定性.%The ethoxyl groups of 3-aminopropyl triethoxysilane (3-APTES),as a surface modifier,reacted with hydroxyls of SnO2.SiO2 was grafted on the surface of SnO2 to inhibit the growth of the SnO2 nanocrystal.Assynthesized samples were characterized by SEM,TEM,FT-IR,XRD and EDS.The results show that the SiO2 remains strongly bonded at the SnO2 surface through Sn—O—Si bonds,the average particle size of modified SnO2 is only 10nm after 1000℃ calcination.However,that of pure SnO2 is 95nm at the same calcination.The well-dispersed SiO2 as a second phase resists the movement of grain boundary and increased the activation ener gy of crystal growth.Nanocrystal growth of SnO2 is effectively restricted up to 1000 ℃.So the thermal stability of SnO2 has been improved.
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