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用高温光电子谱和热重分析方法研究了SrTiO3 纳米微晶材料表面 .结果表明热力学平衡过程中各种离子在晶粒边界附近发生迁移和再分布以及晶格氧和气相氧间的相互转换 ,导致表面组分随着温度发生非常明显的变化 .温度上升时体内的晶格氧离子向晶粒表面迁移 ,同时导致钛离子也向晶粒表面迁移并与表面的氧离子形成Ti O团 .温度下降时则发生相反过程 ,但后一过程比前一过程慢得多 .提出一个初步的模型解释这一过程 .
The surface of SrTiO3 nanocrystalline materials was investigated by high-temperature photoelectron spectroscopy and thermogravimetric analysis. The results show that the various ions migrate and redistribute near the grain boundaries and the interconversion between lattice oxygen and oxygen in the thermodynamic equilibrium process, resulting in The surface composition changes obviously with the temperature.When the temperature rises, the lattice oxygen ions in the body migrate to the grain surface, at the same time, the titanium ions also migrate to the grain surface and form TiO clusters with the surface oxygen ions. The opposite process occurs, but the latter process is much slower than the previous one. A preliminary model is proposed to explain this process.