Optical and structural investigations on titanium oxynitride films for visible-UV photocatalytic applications
Optical and structural investigations on titanium oxynitride films for visible-UV photocatalytic applications
复制标题
DOI：
10.1063/1.5143609
复制
发表时间：
2020-04-07
影响因子：
3.2
通讯作者：
Ohtomo, Akira
中科院分区：
文献类型：
--
作者：
Mizushiro, Jun;Yoshimatsu, Kohei;Ohtomo, Akira
本文报道了利用脉冲激光沉积技术在α-Al_2 O_3（0001）衬底上外延生长氮氧化钛（TiOxNy）薄膜及其光学性质。以TiN为固体源，通过改变O2-气体的分压来调节薄膜中的N含量（y）。结晶相被认为是从岩盐型或金红石型结构演变到y约为0.4。薄膜的光学吸收光谱在0.44-2.4 eV和2.4-6 eV区域有两个不同的分量，分别来自d-d跃迁和电荷转移跃迁。前一个跃迁随着y的减小而减小，并在y接近0.26时消失，其中发现由于后一个跃迁的基本吸收边为2.4 eV。结果表明，在TiOxNy的阴离子组合物的范围是适合于可见光采集应用。由AIP Publishing授权出版。
We report on the epitaxial growth of titanium oxynitride (TiOxNy) films on alpha-Al2O3 (0001) substrates by using a pulsed-laser deposition technique and their optical properties. Using TiN as a solid source, N content (y) in the films was tuned by changing the partial pressure of O-2 gas. The crystalline phase was found to evolve up to y approximate to 0.4 either from rock-salt type or from rutile-type structures. The optical absorption spectra of the films had two distinct components in regions of 0.44-2.4 eV and 2.4-6 eV, which arise from d-d and charge-transfer transitions, respectively. The former transition decreased with decreasing y and vanished at y approximate to 0.26, where a fundamental absorption edge due to the latter transition was found to be 2.4 eV. The results demonstrate a range of anion compositions in the TiOxNy being suitable for visible-light harvesting applications. Published under license by AIP Publishing.