高温高压合成CeTbO3+δ的XPS研究

 经过高温高压合成的CeTbO_3+δ进行了XPS研究，发现在1.0 GPa下，Tb⁴⁺在~600 ℃开始转变成Tb³⁺，而Ce⁴⁺在~800 ℃开始向Ce³⁺转变。在1 000~1 200 ℃形成单相萤石结构化合物CeTbO_3+δ的Ce是以Ce³⁺、Ce⁴⁺混合价形式存在，Tb全部变成Tb³⁺。实验表明，用Ce_3d谱上~888 eV峰的峰位及其与882 eV峰的相对强度变化可以定性判断化合物中是否含有Ce³⁺。研究了高温高压合成的CeTbO_3+δ的稳定性随时间的变化问题。

The XPS Study of CeTbO3+δ Synthesized by High Pressure and Temperature

The samples of CeTbO_3+δ synthesized by high pressure and high temperature were studied by XPS. It is found that Tb⁴⁺ ion begins to transform to Tb³⁺ at about 600 ℃ and Ce⁴⁺ to Ce³⁺ about 800 ℃. The single phase compound of CeTbO_3+δ having a fluorite structure is formed at 1000 ℃, in which the Ce ions exist in a mixed valence state of Ce³⁺ and Ce⁴⁺. The existence of Ce³⁺ ions in compounds can be determined by the shift of the 888 eV photoelectron peak and the change of the relative intensity between this peak and the 882 eV peak. The stability of CeTbO_3+δ synthesized by high pressure and temperature with the time was investigated.