BaTiO3纳米晶机械力化学合成

在氮气保护下，采用高能球磨BaO，锐钛矿型TiO2混合粉体，机械力化学法成功地合成了BaTiO3纳米晶，并讨论了反应机制。发现在一定操作参数条件下，粉磨初期为无定形形成期（15h以前），混合物颗粒粒度减小，晶格畸变，转变为无定形；粉磨中期为固相反应期（15－30h），BaO与TiO2在机械力的作用下产生固相反应生成BaTiO3，同时BaTiO3晶粒长大；粉磨后期又转入动态平衡期（30h以后），固相反应基本结束，已生成的BaTiO3的晶粒生长与粉磨引起的晶粒减小处于动态平衡；XRD，SEM，TEM研究表明：合成BaTiO3纳米晶体的晶粒尺寸为10－30nm。

Nano-Crystalline BaTiO3 Synthesized by Mechanochemistry

The nano-crystalline BaTiO3 was successfully synthesized by grinding the mixture of BaO and anatase TiO2 in a high-energy mill in nitrogen atmosphere and its mechanism was also discussed. The results suggested that the first stage of mechanochemical treatment in initial 15h resulted in the occurrence of decreasing of crystalline size and distorting of crystalline lattice together with amorphization in the mixture powder. BaTiO3 phase was formed by solid reaction in the mixture powder mechanochemically for 15h to 30h at the second stage. In the meantime the crystalline particle grew up. At the last stage of further treatment after 30h the crystalline size of synthesized BaTi03 almost didn't change, because the growing and decreasing of crystalline particle was in a dynamic equilibrium. The crystalline sizes of synthesized BaTiO3 by mechanochemistry were in the range of 10 to 30nm by XRD, SEM and TEM.