摘要
The phase stability of nanocrystaline anatase and rutile TiO2 in sols peptized at different temperature has been studied by X-ray Diffraction (XRD) and thermodynamical analysis. The results show that the stability of nanocrystaline TiO2 of different crystal types is a function of particle size. According to the thermodynamical analysis, anatase TiO2 becomes more stable than rutile TiO2 when the particle size is less than ca. 14 nm, which coincides with the experimental data obtained by XRD. Both surface Gibbs free energy and surface stress play important roles in the thermodynamically phase stability. Comparing the data calculated thermodynamically with the experimental results obtained under different temperatures, it is found that the constant K in the function relation, f=KGS, between surface free energy GS and surface stress f is temperature dependent and equal to 1 at 333 K and 2 at 453 K, respectively.
The phase stabilitv of nanocrvstaline anatase and rutile TiO2 in sols peptized at different temperature has been studied by X-ray Diffraction （XRD） and thermodvnamical analvsis. The results show that the stability of nanocrvstaline TiO2 of different crystal types is a function of particle size. According to the thermodvnamical analysis, anatase TiO2 becomes more stable than rutile TiO2 when the particle size is less than ca. 14 nm. which coincides with the experimental data obtained bv XRD. Both surface Gibbs free energy and surface stress play important roles in the thermodynamically phase stability. Comparing the data calculated thermodynamically with the experimental results obtained under different temperatures, it is found that the constant K in the function relation, f=KG^＋. between surface free energy Gs and surface stress f is temperature dependent and equal to 1 at 333 K and 2 at 453 K. respectively.
出处
《无机化学学报》
SCIE
CAS
CSCD
北大核心
2007年第3期494-498,共5页
Chinese Journal of Inorganic Chemistry
基金
浙江省自然科学基金(No.Y406066)
教育部新世纪优秀人才支持计划(No.NCET-04-0557)资助项目
关键词
纳米TIO2
胶溶
水热晶化
XRD
nanocrystaline TiO2
peptization
hydrothermal crystallization
XRD
