Effects of surface oxygen vacancies on photophysical and photochemical processes of Zn-doped TiO2 nanoparticles and their relationships
Effects of surface oxygen vacancies on photophysical and photochemical processes of Zn-doped TiO2 nanoparticles and their relationships
复制标题
表面氧空位对Zn掺杂TiO2纳米颗粒光物理和光化学过程的影响及其关系。
DOI：
10.1021/jp063148z
复制
发表时间：
2006-09-14
影响因子：
3.3
通讯作者：
Fu, Honggang
中科院分区：
文献类型：
--
作者：
Jing, Liqiang;Xin, Baifu;Fu, Honggang
本文采用溶胶凝胶法制备了不同锌掺杂量的纳米二氧化钛，并用X射线光电子能谱(XPS)、光致发光光谱(PL)和表面光电压谱(SPS)对其进行了表征。研究了掺锌二氧化钛纳米颗粒表面氧空位对光物理和光催化过程的影响及其内在联系。结果表明，SOV很容易与光生电子结合，进而产生荧光信号。SOV能在TiO(2)样品的带边附近产生一个有趣的亚带SPS响应，除了明显的带间SPS响应外，其余都是由大量的锐钛矿和少量的金红石组成。此外，掺入适量的锌还可以增强TiO2光催化降解苯酚溶液的发光强度和SPS信号强度。这些改善主要归因于SOV金额的增加。结果表明，SOV在光致发光、表面光电压和光催化反应过程中起着重要的作用，并且对于550℃热处理的不同掺杂量的样品，SOV越大，光致发光和表面光电子能谱信号越强，光催化活性越高。
In this paper, TiO(2) nanoparticles doped with different amounts of Zn were prepared by a sol-gel method and were mainly characterized by means of X-ray photoelectron spectroscopy (XPS), photoluminescence (PL), and surface photovoltage spectrum (SPS). The effects of surface oxygen vacancies (SOVs) of Zn-doped TiO(2) nanoparticles on photophysical and photocatalytic processes were investigated along with their inherent relationships. The results show that the SOVs easily bind photoinduced electrons to further give rise to PL signals. The SOVs can result in an interesting sub-band SPS response near the band edge in the TiO(2) sample consisting of much anatase and little rutile, except for an obvious band-to-band SPS response. Moreover, the intensities of PL and SPS signals of TiO(2), as well as the photocatalytic activity for degrading phenol solution, can be enhanced by doping an appropriate amount of Zn. These improvements are mainly attributed to the increase in the SOV amount. It can be suggested that the SOVs should play an important role during the processes of PL, surface photovoltage, and photocatalytic reactions, and, for the as-prepared TiO(2) samples doped with different amounts of Zn by thermal treatment at 550 degrees C, the larger the SOV amount, the stronger the PL and SPS signal, and the higher the photocatalytic activity.