Department of Chemistry and Biochemistry, Kent State University , Kent, Ohio 44242, United States.
ACS Appl Mater Interfaces. 2014 Aug 13;6(15):13069-78. doi: 10.1021/am5028742. Epub 2014 Jul 14.
Incorporation of basic species such as amine-containing groups into porous materials is a well-established strategy for achieving high uptake of acidic molecules such as CO2. This work reports a successful use of the aforementioned strategy for the development of ordered mesoporous organosilica (OMO) with amidoxime groups for CO2 sorption. These materials were prepared by two-step process involving: (1) synthesis of OMO with cyanopropyl groups by co-condensation of (3-cyanopropyl)triethoxysilane and tetraethylorthosilicate in the presence of Pluronic P123 triblock copolymer under acidic conditions, and (2) conversion of cyanopropyl groups into amidoxime upon treatment with hydroxylamine hydrochloride under suitable conditions. The resulting series of amidoxime-containing OMO was prepared and used for CO2 sorption at low (25 °C) and elevated (60, 120 °C) temperatures. These sorbents exhibited relatively high adsorption capacity at ambient conditions (25 °C, 1 atm) and remarkable high sorption uptake (∼3 mmol/g) at 60 and 120 °C. This high CO2 uptake at elevated temperatures by amidoxime-containing OMO sorbent makes it a noticeable material for CO2 capture.
将含胺基等基本官能团引入多孔材料中是一种行之有效的策略，可用于实现对酸性分子（如 CO2）的高吸收。本工作成功地利用上述策略，开发了具有偕胺肟基团的有序介孔有机硅（OMO），用于 CO2 吸附。这些材料是通过两步法制备的，包括：（1）在酸性条件下，使用 Pluronic P123 三嵌段共聚物，由（3-氰丙基）三乙氧基硅烷和正硅酸乙酯共聚合成含有氰丙基的 OMO；（2）在适当的条件下，用盐酸羟胺将氰丙基转化为偕胺肟。制备了一系列含有偕胺肟的 OMO，并用于在低温（25°C）和高温（60、120°C）下的 CO2 吸附。这些吸附剂在环境条件（25°C，1 大气压）下表现出相对较高的吸附容量，在 60 和 120°C 下表现出显著的高吸附量（约 3 mmol/g）。偕胺肟官能团的 OMO 吸附剂在高温下具有较高的 CO2 吸收能力，使其成为一种值得注意的 CO2 捕获材料。
