强大的功能化的有机框架,在CO2循环添加上提供卓越的催化性能,使用环氧化物和Knoevenagel凝结
Chong Li1, Hongxiao Lv1, Kun Yang2
1Shanxi Key Laboratory of Advanced Carbon Based Electrode Materials, School of Chemistry and Chemical Engineering, North University of China, Taiyuan 030051, P. R. China.
ACS applied materials & interfaces
|July 12, 2023
概括
新的兰化物有机框架 (LnOFs) 显示出作为催化剂的前景. 这些基于{Ln5}的NUC-61材料具有高的CO2/CH4选择性,并有效催化有机反应,提供稳定可回收的催化平台.
科学领域:
- 材料科学 材料科学 材料科学
- 催化剂是一种催化剂.
- 无机化学 无机化学
背景情况:
- 兰化有机框架 (LnOFs) 由于Ln3+离子的高协调数,它们的催化潜力得到了认可.
- 基于集群的LnOF的探索性合成对于开发新型催化材料至关重要.
- 功能化连接体可以为金属有机框架赋予独特的特性.
研究的目的:
- 为了合成和表征基于新型的3D兰化物有机框架 (LnOFs).
- 研究这些新材料的气体吸附特性,特别是CO2/CH4选择性.
- 评估在有机反应中合成的LnOFs的催化活性.
主要方法:
- 使用{Ln5}集群和功能化四联体 (F-H4PTTA) 的等态纳米孔状框架的热水合成.
- 对易斯酸位 (开放的LnIII位,μ3-OH, -F) 的激活框架 (NUC-61a) 的表征.
- 使用理想吸附溶液理论 (IAST) 和催化性能测试进行气体吸附测量 (CO2/CH4).
主要成果:
- 两个强大的,基于等态{Ln5}的3D框架,NUC-61 (Ln = Ho, Dy),与纳米子空洞成功合成.
- 激活的NUC-61Ho-a在298K时表现出高的CO2/CH4吸附选择性 (在50/50时12.7,在5/95时9.1),使得高纯度的CH4.4成为可能.
- NUC-61Ho-a有效催化二氧化碳循环添加与环氧化物和诺维纳格尔凝结反应.
结论:
- 基于{Ln5}的NUC-61框架很少见,并且具有独特的纳米空洞.
- 激活的NUC-61a材料表现出丰富的易斯酸基位,有助于它们的功能.
- NUC-61材料表现出卓越的化学稳定性,异质性和可回收性,证明了它们作为双功能酸催化剂的潜力.
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