Department of Earth and Environmental Engineering, Lenfest Center for Sustainable Energy, Columbia University New York, New York 10027, United States.
Environ Sci Technol. 2011 Aug 1;45(15):6633-9. doi: 10.1021/es200146g. Epub 2011 Jun 30.
Novel liquid-like nanoparticle organic hybrid materials (NOHMs) which possess unique features including negligible vapor pressure and a high degree of tunability were synthesized and their physical and chemical properties as well as CO(2) capture capacities were investigated. NOHMs can be classified based on the synthesis methods involving different bonding types, the existence of linkers, and the addition of task-specific functional groups including amines for CO(2) capture. As a canopy of polymeric chains was grafted onto the nanoparticle cores, the thermal stability of the resulting NOHMs was improved. In order to isolate the entropy effect during CO(2) capture, NOHMs were first prepared using polymers that do not contain functional groups with strong chemical affinity toward CO(2). However, it was found that even ether groups on the polymeric canopy contributed to CO(2) capture in NOHMs via Lewis acid-base interactions, although this effect was insignificant compared to the effect of task-specific functional groups such as amine. In all cases, a higher partial pressure of CO(2) was more favorable for CO(2) capture, while a higher temperature caused an adverse effect. Multicyclic CO(2) capture tests confirmed superior recyclability of NOHMs and NOHMs also showed a higher selectivity toward CO(2) over N(2)O, O(2) and N(2).
新型液态纳米有机杂化材料（NOHM）被合成出来，其具有独特的性质，包括极低的蒸气压和高度的可调性。研究了它们的物理化学性质和 CO2 捕获能力。NOHM 可以根据涉及不同键合类型、存在连接体以及添加特定任务的功能基团（如胺用于 CO2 捕获）的合成方法进行分类。由于聚合物链的冠层被接枝到纳米颗粒核心上，因此所得 NOHM 的热稳定性得到了提高。为了在 CO2 捕获过程中隔离熵效应，首先使用不含对 CO2 具有强化学亲和力的官能团的聚合物来制备 NOHM。然而，人们发现，即使聚合物冠层上的醚基团也通过路易斯酸碱相互作用有助于 NOHM 中的 CO2 捕获，尽管与胺等特定任务的官能团的影响相比，这种影响微不足道。在所有情况下，较高的 CO2 分压更有利于 CO2 捕获，而较高的温度则产生不利影响。多循环 CO2 捕获测试证实了 NOHM 的优异可回收性，并且 NOHM 对 CO2 相对于 N2O、O2 和 N2 的选择性也更高。
