通过调节Ru-Promoter接口,通过Ru催化剂提升N2转化为NH3的速度
Kailin Su1, Dongya Huang1, Hongpeng Fang1
1National Engineering Research Center of Chemical Fertilizer Catalyst, Fuzhou University, Fuzhou, Fujian 350002, China.
ACS applied materials & interfaces
|November 28, 2023
概括
改变 (Ba) 和 (Ru) 物种的加载序列可显著增加氨 (NH3) 合成. 在石墨碳 (GC) 上预先加载Ba,通过优化Ru-促进器接口以激活N2来提高催化剂性能.
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
- 化学工程是化学工程的重要组成部分.
背景情况:
- 促进剂对于氨 (NH3) 合成中的 (Ru) 基催化剂至关重要,特别是对于 (N2) 激活.
- 促进体的排列和类型显著影响NH3合成速率.
研究的目的:
- 为了研究改变 (Ba) 和Ru物种的加载序列对石墨碳 (GC) 支持NH3合成的影响.
- 通过简单的加载序列修改优化Ru-促进器接口来提高NH3合成速率.
主要方法:
- 合成了Ba-Ru/GC和Ru-Ba/GC催化剂,通过改变Ba和Ru物种的加载序列在石墨碳支上.
- 通过测量在400°C和1MPa的NH3合成速率来评估催化剂性能.
- 利用表征技术来分析催化剂结构,分散和电子特性.
主要成果:
- 在之前加载Ba的Ba-Ru/GC催化剂,实现了NH3合成速率18.7 mmolgcat-1h-1.1.
- 这一速率是Ru-Ba/GC催化剂的2.5倍,该催化剂由传统的Ru-first加载制备.
- 之前的Ba负载导致了Ba的高分散,小Ru粒子的稳定,并增强了Ba向Ru的电子捐赠.
结论:
- 促进体的加载序列对Ru-促进体接口和NH3合成中的催化活性产生关键影响.
- 预先将Ba加载到GC上,有效地分散促进剂并稳定Ru,最大限度地提高N2激活的活性位点.
- 这一策略提供了一种简单而有效的方法,通过优化促进剂利用来提高NH3合成性能.
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