反应温度和时间对Bi_2SiO_5合成的影响  

Effects of reaction temperature and time on synthesis of Bi_2SiO_5

作　　者：王燕[1] 王秀峰[1] 于成龙[1] 田清泉[1] 

机构地区：[1]陕西科技大学材料科学与工程学院,陕西咸阳712081

出　　处：《无机盐工业》2007年第4期38-40,共3页Inorganic Chemicals Industry

摘　　要：亚稳相Bi2SiO5是Bi2O3-SiO2系统最新发现的化合物晶相。利用XRD,DSC研究了反应温度和时间对Bi2SiO5合成的影响。将Bi2O3与SiO2按物质的量比1∶1混合,在一定温度下处理一定时间获得生成产物。结果表明:亚稳化合物Bi2SiO5在固相反应时产生,并随温度及保温时间按一定规律变化。固相反应温度由700℃升高至900℃过程中,亚稳态Bi2SiO5逐渐转变为稳定态Bi12SiO20和Bi4Si3O12,反应温度对Bi2SiO5的生成起决定性作用。750℃保温不同时间所获试样的XRD谱表明,固相反应时间延长,反应物Bi2O3的衍射峰减弱,稳定相Bi12SiO20衍射峰增强,随着反应的进行,生成物亚稳相Bi2SiO5的衍射峰减弱,反应时间过长,不利于亚稳相Bi2SiO5生成。Metastable state Bi2SiO5 is a newly discovered compound crystalling phase in Bi2O3 -SiO2 system. The effects of reaction temperature and time on the formation of Bi2SiO5 were studied by XRD and DSC. The mixture of Bi2O3 and SiO2 , which were mixed with amount - of - substance ratio of 1： 1, was treated under a certain temperature for a certain period of time to get the product. The results showed that the metastable state compound - Bi2SiO5 was got while solid - state reaction happened,and it varied following the change of temperature and heat preservation time according to a certain law. Metastable state Bi2 SiO5 changed into stable state Bi12SiO20 and Bi4 Si3 O12 gradually when temperature of solid- state reaction rose from 700℃ to 900℃. Therefore,reaction temperature played a crucial role in the formation of Bi2SiO5. XRD was made on the samples getting from different heat preservation time at 750 ℃ and the diffraction figures showed that：instead of strengthened,the product＇s （ metastable state Bi2SiO5） diffraction peak fell off while the solid reaction time was prolonged,the diffraction peak of stable state Bi12SiO20 strengthened by following the weakening of reactant＇s （ Bi2O3 ） diffraction peak and the reaction became more and more complete. Therefore,excessively long reaction time goes against the formation of metastable state Bi2 SiO5.

关 键 词：亚稳Bi2SiO5 固相反应 Bi2O3-SiO2 

分 类 号：TQ170.1[化学工程—硅酸盐工业]