高选择性和尖的火山类型协同Ni2Pt@ZIF-8-催化进化从氨基水解
Fangyu Fu1, Changlong Wang1,2, Qi Wang1
1ISM, UMR CNRS No. 5255 , Université de Bordeaux , 33405 Talence Cedex , France.
Journal of the American Chemical Society
|July 12, 2018
概括
使用ZIF-8支持的新型双金属- (Ni2Pt) 纳米粒子实现了高效的 (H2) 生产. 这种催化剂表现出了显著的协同作用,并优于现有的H2生成方法.
科学领域:
- 材料科学
- 催化剂
- 纳米技术
背景情况:
- 氨水解为安全和快速 (H2) 生产提供了一个有前途的途径.
- 有效的催化对于释放的潜力至关重要.
研究的目的:
- 开发和优化用于酸水解的高效双金属纳米粒子催化剂.
- 为了研究和在化胺酸框架 (ZIF-8) 支持H2的协同效应.
主要方法:
- 几乎单分散的合金双金属Ni-Pt纳米粒子的合成.
- 在ZIF-8支上固定纳米粒子.
- 在包括NaOH在内的各种条件下对氨基水解进行催化试验.
- 动态研究,包括使用D2O的动态同位素效应,以阐明反应机制.
主要成果:
- 优化的Ni2Pt@ZIF-8催化剂在H2释放方面表现出卓越的效率和选择性,超过单个Ni或Pt催化剂.
- 最好的催化剂在环境条件下达到600 molH·molcatal-1和2222 molH·molPt-1.
- NaOH与Ni2Pt@ZIF-8显著增强了H2进化,但与Pt@ZIF-8抑制了它,表明了独特的协同作用.
- 机械研究确定了通过氧化添加的O-H键裂变作为速度决定的步骤.
结论:
- 在ZIF-8中嵌入的合金Ni-Pt纳米颗粒代表了酸水解的高效催化系统.
- 观察到的Ni和Pt之间的积极协同作用,加上ZIF-8支的性能,为H2生成提供了显著的进步.
- 这项工作为未来从富含基材生产方便的催化剂铺平了道路.
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