The present invention provides a functional metal-organic framework (MOF) comprising a base metal-organic framework and a polymer formed within pores of the base metal-organic framework, wherein the base metal-organic framework comprises a metal having open coordination sites (OCS) and the polymer is formed by polymerization of an unsubstituted aniline; an aniline substituted with at least one substituent selected from the group consisting of halo, C1-C3 alkyl, C1-C3 haloalkyl, C1-C3 alkoxy, and hydroxy; or a combination thereof.
