非晶二氧化钛电致变色薄膜中的离子俘获与反俘获研究

电致变色薄膜可以控制可见光和红外光的透过率，因此被广泛应用于智能窗领域。在微小电场（0-3伏）调节下，它可以有效地改变室内的明暗强度以及温度。因此，近年来人们对于电致变色材料的需求日益增加。尽管开发用于改进电致变色器件性能的新型材料非常重要，但减少甚至消除电致变色材料在工作过程中的性能退化同样是一个关键科学问题。二氧化钛作为一种无机电致变色材料被广泛研究，其性能在长时间循环后的退化是不可能避免的。有限的使用寿命极大地阻碍了二氧化钛作为电致变色材料的商业化应用。因此本文研究二氧化钛电致变色性能退化的原因并探索了使其性能恢复的方法。

本课题采用磁控溅射法在氧化铟锡玻璃衬底上制备得到了厚度在270纳米左右的非晶二氧化钛薄膜。所制备的薄膜结构完整且具有良好的电致变色性能。通过电化学-原位光谱测试、X射线衍射、扫描电子显微镜、X射线光电子能谱等表征手段，对薄膜的结构、性能退化的过程、原因以及恢复方法进行了深入的研究。

结果表明二氧化钛薄膜在工作过程中的性能衰减是由于嵌入离子被俘获在主体材料内部所致。根据施加在二氧化钛薄膜所的电压窗口不同，当插入的离子被浅层俘获位点俘获时，会导致薄膜的着色态单调衰减；而当离子被深层俘获位点以及改性的浅层俘获位点俘获时，薄膜的着色态与漂白态会同时发生衰减。同时，俘获位点中的离子可通过反俘获过程得以释放，从而使二氧化钛薄膜恢复其初始性能。此外，实验探究了非晶二氧化钛中不同离子俘获位点的能量关系与形成过程，并论证了非晶二氧化钛中的可逆位点与各个俘获位点是可以通过离子的俘获和反俘获相互转换。

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