Air-thermal processing of hierarchically porous metal-organic frameworks
Air-thermal processing of hierarchically porous metal-organic frameworks
复制标题
分级多孔金属有机框架的空气热处理
DOI：
10.1039/d0nr02899a
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发表时间：
2020
期刊：
影响因子：
6.7
通讯作者：
Li Wanbin
中科院分区：
文献类型：
--
作者：
Jia Miaomiao;Mai Lei;Li Zhanjun;Li Wanbin
金属有机框架（MOF）在各种应用中显示出巨大的潜力。 MOFs的功能与其多孔结构和晶格完整性密切相关。然而，普遍存在的客体溶剂/连接分子和晶体缺陷会改变MOF的内部微观结构和微环境。同时，尽管MOF在小孢子范围内具有可定制的孔结构，但MOF中介孔/大孔的实现具有科学意义。在此，报道了一种多功能空气热处理（ATP）策略，可以去除 MOF 中的残留分子和不完全协调的连接体。通过在有限空间内加工MOF，热化和加压的空气可以帮助填充溶剂和部分/完全不协调的连接体克服逃逸的能量障碍，然后最大化MOF的孔隙率。所得具有分级微/介孔结构的MOF材料显示出显着提高的吸附容量和选择性。例如，CuBTC-A 的表面积、孔体积、CO2 吸收和 CO2/N2 选择性分别提高了 36%、72%、22% 和 86%。此外，通过调整加工温度，ATP策略可用于在无调制器/模板条件下制造具有分级微/介观/大孔超结构的MOF材料。
Metal–organic frameworks (MOFs) show great potential for various applications. The functions of MOFs are closely related to their porous structures and lattice integrities. However, the generally existing guest solvent/linker molecules and crystalline defects will alter internal microstructures and microenvironments of MOFs. Meanwhile, although MOFs have tailorable pore structures within the range of microspores, the achievement of meso/macropores in MOFs is of scientific interest. Herein, a versatile air-thermal processing (ATP) strategy is reported to remove the residual molecules and incompletely coordinated linkers in MOFs. Through processing MOFs in confined space, the thermalized and pressurized air can assist the filling solvents and partially/totally uncoordinated linkers to overcome the energy barrier of escape, and then maximize MOF porosity. The obtained MOF materials with hierarchical micro/mesoporous structures display substantially improved adsorption capacities and selectivities. For example, CuBTC-A shows 36%, 72%, 22%, and 86% enhancements in surface area, pore volume, CO2 uptake, and CO2/N2 selectivity, respectively. Moreover, by adjusting processing temperature, the ATP strategy is available for fabricating MOF materials with hierarchically micro/meso/macroporous superstructures under modulator/template-free conditions.