A synthetic route to ultralight hierarchically micro/mesoporous Al(III)-carboxylate metal-organic aerogels

• Published in: Nature communications Vol. 4; no. 1; p. 1774
• Main Authors: Li, Lei, Xiang, Shenglin, Cao, Shuqi, Zhang, Jianyong, Ouyang, Gangfeng, Chen, Liuping, Su, Cheng-Yong
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 30.04.2013; Nature Publishing Group; Nature Pub. Group
• Subjects: 639/301/923/1027; 639/301/930/1032; 639/638/298/921; Catalysis; Crystallization; Humanities and Social Sciences; multidisciplinary; Porous materials; Science; Science (multidisciplinary)
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/ncomms2757

Developing a synthetic methodology for the fabrication of hierarchically porous metal-organic monoliths that feature high surface area, low density and tunable porosity is imperative for mass transfer applications, including bulky molecule capture, heterogeneous catalysis and drug delivery. Here we report a versatile and facile synthetic route towards ultralight micro/mesoporous metal-organic aerogels based on the two-step gelation of metal-organic framework nanoparticles. Heating represents a key factor in the control of gelation versus crystallization of Al(III)-multicarboxylate systems. The porosity of the resulting metal-organic aerogels can be readily tuned, leading to the formation of well-ordered intraparticle micropores and aerogel-specific interparticle mesopores, thereby integrating the merits of both crystalline metal-organic frameworks and light aerogels. The hierarchical micro/mesoporosity of the Al-metal-organic aerogels is thoroughly evaluated by N 2 sorption. The good accessibility of the micro/mesopores is verified by vapour/dye uptake, and their potential for utilization as effective fibre-coating absorbents is tested in solid-phase microextraction analyses. Hierarchically porous metal-organic monoliths are potential materials for mass transfer applications. Here, the authors synthesize metal-organic aerogels via the gelation of metal-organic frameworks, and are able to tune their porosity exploiting the properties of both crystalline and aerogel materials.