在微乳液衍生氧化物上自发生成单片氧,具有富氧空缺,用于高效的有氧氧化
Jun Tang1,2, Junbao Chen1, Zhanyu Zhang1
1College of Chemistry and Chemical Engineering, Anhui University of Technology Maanshan 243002 Anhui P. R. China Qingke@ahut.edu.cn.
Chemical science
|November 30, 2023
概括
氧化物纳米催化剂在室温下直接产生单片氧 (1O2),用于绿色化学合成. 这项创新增强了酒精的有氧氧化,达到99%以上的产量和出色的可回收性.
科学领域:
- 材料科学 材料科学 材料科学
- 催化剂是一种催化剂.
- 绿色化学 绿色化学
背景情况:
- 有效地将分子氧 (O2) 激活成单片氧 (1O2) 对绿色化学合成至关重要,但面临实际实施的挑战.
- 当前的方法往往需要外部字段或特定条件,限制了它们的适用性.
研究的目的:
- 设计和合成能够在室温下直接单片氧气生成的氧化物 (N-MnO2) 纳米催化剂.
- 调查缺陷工程和兴奋剂在提高O2激活和催化性能方面的作用.
- 为了证明这些纳米催化剂在室温有氧氧化反应中的应用.
主要方法:
- 合成N-化氧化 (Nx-MnO2) 纳米催化剂,使用分隔微乳液结晶和后化.
- 纳米催化剂性能的表征,包括表面氧空缺 (Ov) 和间歇含量.
- 使用电子磁共振光谱和反应性氧物种捕获实验验证1O2生成.
- 密度函数理论 (DFT) 计算,以了解O2激活的机制.
- 在酒精的有氧氧氧化过程中测试催化性能.
主要成果:
- 优化的N55-MnO2纳米催化剂在氧空隙附近呈现出高度的表面氧原子 (51.1%) ,促进了O2的化学吸收和激活.
- 在没有外部场的情况下,在室温下确认了1O2的自发生成.
- 在酒精的有氧氧氧化中,N55-MnO2的产量超过99%,与未使用的MnO2.2相比,提高了6.7倍.
- 该纳米催化剂在醇的有氧氧化转化过程中,在10个循环中表现出极好的可回收性.
结论:
- 在MnO2纳米催化剂中的兴奋剂和缺陷工程有效地促进在室温下自发O2激活到1O2.
- 开发的N55-MnO2纳米催化剂为精细化学品的绿色有氧氧化合成提供了高效和可回收的解决方案.
- 这种方法为可持续的化学转化提供了一个有希望的途径.
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