了解可持续聚合物的双核聚合催化剂的催化协同作用
Francesca Fiorentini1, Wilfred T Diment1, Arron C Deacy1
1Department of Chemistry, University of Oxford, OX1 3TA, Oxford, United Kingdom.
Nature communications
|August 8, 2023
概括
具有地球丰富金属的新型异质核催化剂在多重聚合过程中显示出可预测的性能. 在s块金属中较低的易斯酸度与更高的催化速率和选择性相关,指导未来的催化剂设计.
科学领域:
- 催化剂是一种催化剂.
- 聚合物化学 聚合物化学
- 材料科学 材料科学 材料科学
背景情况:
- 从地球上丰富的元素开发高效的催化剂对于可持续化学至关重要.
- 了解催化中的结构性能关系,特别是金属间协同作用,仍然是一个重大挑战.
研究的目的:
- 为了评估三种不同的聚合反应的异构核Co (III) M (I/II) 催化剂.
- 建立适用于不同聚合类型的一般结构性能相关性.
- 通过使用廉价和无毒元素,识别具有高性能的催化剂.
主要方法:
- 不同核催化剂的合成和表征 (Co (III) M (I/II),M=Na,K,Ca,Sr,Ba).
- 催化性能的评估,包括速率常数,周转频率,选择性和控制在CO2/氧化物环开合聚合 (ROCOP),氧化物/甲化物 ROCOP和乳化物环开聚合 (ROP) 中.
- 催化剂性能与易斯酸度的相关性分析 (pK_a of [M(OH2) m]n+).
主要成果:
- 具有较低易斯酸度的s块金属的催化剂在所有测试的聚合物中表现出优异的速率和选择性.
- 环氧化物/异构ROCOP活性显示,随着易斯酸度的下降,其指数级增加.
- 乳化物ROP活性和CO2/环氧化物选择性随着易斯酸度的下降呈现线性增加.
结论:
- 确定了对异种核催化剂的清晰和广泛适用的结构-活性/选择性相关性.
- 证明了s块金属在设计高性能,可持续的催化剂方面的潜力.
- 为聚合催化剂的合理催化剂设计和优化提供了一个框架.
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