摘要
提出了一个分散在γ－Ａｌ２Ｏ３表面的金属氧化物单层结构的表面对称模型．该模型认为金属氧化物单层结构符合以下规则：（１）金属氧化物的氧负离子将尽量保持与所在表面层的氧负离子相同的排列方式；（２）金属离子将根据所在表面层金属离子排布的对称性取与之相适应的排布方式；（３）金属离子和氧负离子都对分散单层的结构有影响．根据这些规则，对一价、二价、三价和六价金属氧化物的分散单层的具体形态进行了讨论．该模型预测的单层分散阈值与实验值符合得很好．
A model of the structure of metal oxides supported on γ Al 2O 3 is developed. According to the model, the structure of the metal oxide monolayer abides by the following rules: (1) when the metal oxides dispersed on γ Al 2O 3, the arrangement of the oxygen anions will make the widest use of the oxygen anion arrangement of the support surface; (2) the cations will arrange according to the symmetry of the cations on the support surface; (3) the cations and anions will affect the structure of the dispersion monolayer. The structure of the M +, M 2+ , M 3+ and M 6+ metal oxides is discussed based on the above rules, and the dispersion capacity predicted by the model is in good agreement with the measured values. It is proposed that the dispersion monolayer is an intermediate state.
出处
《催化学报》
SCIE
EI
CAS
CSCD
北大核心
1996年第6期517-521,共5页
基金
国家自然科学基金
关键词
金属氧化物
氧化铝
单层分散
表面对称模型
Metal oxide, Alumina, Monolayer dispersion, Surface symmetry model
