针对选择性初级C-H键氧化的支持Pt催化剂的定制Cl-结合
在PubMed上查看摘要
概括
此摘要是机器生成的。催化剂在选择性氧化反应中经常过度氧化基质. 用化物 (Cl-) 连接物和单个 (Pt) 原子,通过控制Pt活性,提高选择性到100%.
科学领域
- 催化剂
- 材料科学
- 化学工程
背景情况
- (Pt) 金属氧化物催化剂对于选择性氧化至关重要,但由于过度氧化,其选择性较低.
- 实现高选择性需要精确控制Pt活性位点的电子和协调特性.
研究的目的
- 开发一种提高Pt催化选择性氧化反应的策略.
- 研究联体在修改Pt原子行为和催化性能方面的作用.
主要方法
- 在减少的二氧化 (TiO2) 上合成了一种由单个 Pt 原子组成的催化剂系统.
- 具有化物 (Cl-) 连接体的功能化低协调单个Pt原子.
- 描述了催化剂的电子结构和协调环境.
- 在选择性氧化中评估了催化性能.
主要成果
- 联体和将两位坐标的Pt原子转化为四位坐标的无活化配置,防止过度氧化.
- 在烯的初级C-H键氧化产物中达到100%的选择性,从50.1%显著增加.
- 在减少的TiO2中稳定了活性Ti3+位点,使产品的产量达到249. 8 mmolgcat-1.
结论
- 使用联体来修改单个Pt原子协调的策略有效地提高了氧化反应的选择性.
- 这种方法为设计在选择性氧化过程中性能提高的先进催化剂提供了有希望的途径.
相关概念视频
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