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通过Hydrosilane辅助方法制备的相控Co纳米颗粒调节催化化选择性

He Jiang¹, Dian Deng¹, Yusuke Kita²

¹Laboratory for Materials and Structures, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226-8503, Japan.

Journal of the American Chemical Society

|July 18, 2024

概括

一种新的水辅助方法合成了具有不同的晶相 (fcc和hcp) 的纳米粒子. 六角密封 (hcp) 纳米颗粒通过酸化产生选择性胺具有优异的催化活性.

科学领域:

材料科学
催化剂
纳米技术

背景情况:

(Co) 是用于工业化的高贵金属的成本有效替代品.
催化性能与的晶体相有关,但由于合成的挑战,缺乏系统研究.
控制不同晶体阶段的纳米粒子大小和表面积对于比较催化是至关重要的.

研究的目的:

开发一种新的合成不同晶体结构但相似大小的纳米颗粒的方法.
研究面中心立方 (fcc) 和六角密封 (hcp) 纳米颗粒在酸化中的催化性能.
探索使用催化剂从酸中选择性生产胺.

主要方法:

使用纳米粒子合成的水辅助方法.
使用1,3-butanediol和propylene glycol作为溶剂,分别选择性地产生fcc和hcp纳米粒子.
具有相似大小和表面积的纳米粒子,以确保公平的催化比较.

主要成果:

成功合成了具有相似尺寸和表面积的fcc和hcp纳米粒子.
六角密封 (hcp) 纳米颗粒在温和条件下表现出比fcc纳米颗粒更高的催化活性.
在没有添加氨气的情况下,hcp催化剂实现了高度选择性的胺生产,这是其他系统的常见要求.

结论:

用水辅助的方法提供了一个可行的途径,以控制尺寸的纳米颗粒具有不同的晶体相.
Hcp纳米颗粒是酸化中的优质催化剂,能够有效和选择性地合成胺.
机理学见解表明,快速的初级氨基形成和抑制的副作用有助于hcp催化剂的高选择性.

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