在Pd和VOδ上促进反应性氧物种的形成,并将TiO2用于甲氧化成有价值的氧化物
Huanyu Zhou1,2, Fan Chen1,2, Dandan Liu1,2
1College of Materials Science and Engineering, Nanjing Tech University, 30 South Puzhu Road, Nanjing, 211816, China.
Small (Weinheim an der Bergstrasse, Germany)
|February 16, 2024
概括
这项研究引入了一种新的Pd和VOδ联合修改的TiO2催化剂,用于高效的直接甲氧化成有价值的液体氧化物. 催化剂通过利用来增强反应性氧物种的产生,显著提高了产量和选择性.
科学领域:
- 催化剂是一种催化剂.
- 材料科学 材料科学 材料科学
- 环境化学环境化学
背景情况:
- 直接光催化甲氧化是甲利用的关键.
- 不高效的活性氧物种 (ROS) 生产限制了甲 (CH4) 的激活.
- 开发先进的催化剂对于提高甲转化效率至关重要.
研究的目的:
- 开发一种用于将甲直接和选择性氧化成液体氧化物的新型催化剂.
- 研究TiO2上联合修饰的Pd和VOδ在增强甲转化中的作用.
- 了解ROS生产的机制及其对催化性能的影响.
主要方法:
- 合成Pd和VOδ共同修饰的TiO2 (Pd0.5V0.2-TiO2) 催化剂.
- 在O2和H2下进行光催化甲氧化实验.
- 液体氧化物的产量和选择性的分析.
- 研究协同效应和ROS生成机制.
主要成果:
- 优化的Pd0.5V0.2-TiO2催化剂实现了5014μmolg-1h-1的液体氧化物的产率,具有89.3%的选择性.
- 与没有H2的实验相比,添加H2显著提高了性能 (2682μmol g−1 h−1,77.8%的选择性).
- Pd和VOδ之间的协同效应增强了电荷载体的分离,O2的减少和H2O2的产生.
结论:
- Pd和VOδ联合修改的TiO2是直接氧化甲成液体氧化物的高效催化剂.
- 通过H2添加在现场生成的H2O2在促进ROS生产和催化效率方面发挥着关键作用.
- 催化剂证明了在环境温度下可持续利用甲的有希望的途径.
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