了解M(III) 选择在异种核聚合催化剂中的影响
Katharina H S Eisenhardt1, Francesca Fiorentini1, Charlotte K Williams1
1Department Chemistry, University of Oxford, Chemistry Research Laboratory, 12 Mansfield Road, Oxford, OX1 3TA U.K.
Inorganic chemistry
|November 19, 2024
概括
新型和铁催化剂为通过环开放共聚合 (ROCOP) 来生产聚碳酸和聚提供了可持续的替代品. (III) K (I) 催化剂在CO2/环氧化物ROCOP中表现出异常活力,性能优于现有的催化剂.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物化学 聚合物化学
- 催化剂是一种催化剂.
背景情况:
- 环开合聚合 (ROCOP) 的环氧化物与二氧化碳或无水化物是可持续的聚碳酸和聚的关键.
- 目前的催化剂通常依赖于昂贵的,而大量的和铁催化剂的活性较低.
- 使用地球上丰富的金属开发高效,成本有效的催化剂对于工业可扩展性至关重要.
研究的目的:
- 为了合成和评估ROCOP的新型异构核Al (III),Fe (III) 和K (I) 催化剂.
- 为了比较Al (III) K (I),Fe (III) K (I) 和Co (III) K (I) 催化剂在环氧化物聚合中的催化性能.
- 建立基于M(III) 站点电子的结构-活动关系,并指导未来的催化剂设计.
主要方法:
- 新型异构核Al (III) K (I),Fe (III) K (I) 和Co (III) K (I) 催化剂的合成.
- 在四种不同的单体组合 (二氧化碳或无水化物与环氧化物) 的环开放共聚化中评估催化剂性能.
- 使用IR和NMR光谱学,循环电压计和单晶X射线衍射,对M(III) 位点电子的表征.
主要成果:
- (III) K (I) 催化剂在环氧化物 (CHO) / CO2 ROCOP中表现出色的活性,成为以1 bar CO2为报告的最快的基催化剂.
- 在Al (III) K (I),Fe (III) K (I) 和Co (III) K (I) 催化剂中发现了M (III) 电子密度和催化活性之间的明显相关性.
- 对于CO2/环氧ROCOP,Al (III) K (I) 证明优越,而Fe (III) K (I) 则是无水化物/环氧ROCOP的首选,考虑到性能,丰度和成本.
结论:
- 新型Al (III) K (I) 和Fe (III) K (I) 催化剂为ROCOP提供了高效和可持续的替代品.
- 了解金属中心的电子特性对于设计高活性和选择性催化剂至关重要.
- 催化剂Al (III) K (I) 是一个有希望的,具有成本效益的解决方案,可通过二氧化碳利用实现可持续的聚碳酸生产.
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