摘要
用IR、Raman光谱研究了SO2 -4 /TiO2 固体酸在不同烧结温度下的结构、晶相转变和表面酸中心。结果表明 ,SO2 -4 与TiO2 表面的结合为螯合式双配结构。当烧结温度小于 5 0 0℃时 ,SO2 -4 /TiO2 样品具有较高的结构稳定性 ,晶相结构以锐钛矿为主 ,表面B酸位数目约是L酸位数目的 2倍。当烧结温度大于5 0 0℃时 ,随着烧结温度的升高 ,表面结合的SO2 4 逐渐流失 ,晶相从锐钛矿转变为金红石 ,表面B酸位减少并消失。
The structure,crystal phase transition and surface acid centers of SO 2- 4/TiO 2 solid acids calcined at different temperatures were studied by IR and Raman spectroscopy.The results showed that SO 2- 4 is combined with metal ions of TiO 2 in a chelating bidentate mode.When the calcination temperature is below 500 ℃,the samples possess stable structure with anatase as the main crystal phase,and there are two types of acid sites (Lewis and Bronsted acid) on the samples,the amount of B acid is about twice as that of L acid.When the temperature is above 500 ℃,surface SO 2- 4 desorb gradually with increasing calcination temperature,leading to crystal phase transition from anatase to rutile and the surface B acid sites fade away.
出处
《光谱学与光谱分析》
SCIE
EI
CAS
CSCD
北大核心
2000年第6期840-841,共2页
Spectroscopy and Spectral Analysis
基金
国家自然科学基金项目!(批准号 :2 98430 0 3)
国家产业化前期关键技术开发项目!(批准号 :98 0 3)
福建省自然科学基金!(批准号 :B
