黑色泰坦尼亚通过声化学:对现有方法的批判性评估
Arno Raes1, Rajeshreddy Ninakanti1, Lore Van den Bergh2
1Sustainable Energy, Air & Water Technology (DuEL), University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium; NANOlab Center of Excellence, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium.
Ultrasonics sonochemistry
|September 18, 2023
概括
声化学处理不会产生黑色 (TiO2) 缺陷. 探测器侵蚀会污染样品,导致颜色变化,而不是改善光催化. 材料形态的变化是关键.
科学领域:
- 材料科学 材料科学 材料科学
- 化学 化学 化学
- 纳米技术纳米技术
背景情况:
- 黑色 (TiO2) 制造对于在光催化中增强太阳光采集至关重要.
- 像氧气空缺和Ti3+中心这样的缺陷被认为会导致TiO2变黑并提高效率.
- 在声化学处理过程中,声学化被提出作为一种引入这些缺陷的方法.
研究的目的:
- 调查声化学处理在为光催化剂制造TiO2缺陷方面的有效性.
- 为了确定超声波后TiO2粉末颜色变化的原因.
- 重新评估声波TiO2.2所导致的光催化活性所报告的增强.
主要方法:
- 超声波对P25 TiO2粉末的超声波处理在8000 W/L,持续时间不同.
- 使用HAADF-STEM进行结构完整性和污染的分析.
- 通过UV-Vis DRS,DRIFTS和EPR光谱进行表征,以评估表面变化和缺陷.
主要成果:
- 声极端的显著侵蚀污染了TiO2样本,导致观察到的变黑.
- 没有检测到催化剂表面化学 (UV-Vis DRS,DRIFTS) 或显著的Ti3+中心/氧空隙形成 (EPR) 的实质性变化.
- 化学降解的TiO2显示Ti3+度高于超声波样本.
结论:
- 黑化和报告的超声波TiO2的光催化增强主要是由于sonotrode侵蚀和形态变化,而不是缺陷的产生.
- 声化学合成需要仔细考虑探头侵蚀作为一个混因素.
- 通过超声波来改善光催化物的真正黑色TiO2的制造仍然没有被这项研究证明.
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