不和五角协调Mo5c5+站点使以中C-H键的低温氧化成为可能
Qi Yang1,2, Xiujuan Gao1,2, Faen Song1
1State Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan 030001, Shanxi, China.
JACS Au
|November 30, 2023
概括
研究人员确定了不和五协调Mo5c5+作为二甲基乙烯 (DME) 氧化活性位点. 这一突破使得在低温下选择性C-H键氧化成为可能,从而产生高甲基甲酸盐选择性.
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
- 纳米技术纳米技术
背景情况:
- 选择性C-H键氧化对于与能量相关的分子至关重要,但在温和条件下具有挑战性.
- 含有Mo5+物种的氧化纳米结构显示出希望,但活性部位和机制尚不清楚.
研究的目的:
- 在氧化纳米结构中确定活性Mo5+物种的精确结构.
- 阐明二甲基乙醇 (DME) 低温氧化的催化机制.
主要方法:
- 氧化物纳米结构的热水合成.
- 先进的特征化技术 (ESR,XPS) 进行分析.
- 密度函数理论 (DFT) 的计算.
- 对DME氧化的催化活性测试.
主要成果:
- 确定了不和的五分协调Mo5c5+物种作为活性位点.
- 在110°C达到96.3%的甲基甲酸盐选择性和12.5%的DME转化.
- 通过设计实验,在现场确认了Mo5c5+物种的形成.
结论:
- 五角协调的Mo5c5+位点是高效低温DME氧化的关键.
- 五慢性位在较低温度下促进CH3O*中C-H键的氧化.
- 这项工作澄清了基于的催化剂中的活性位点和机制.
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