title: Evolution of form in metal-organic frameworks.
abstract: Self-assembly has proven to be a widely successful synthetic strategy for functional materials, especially for metal-organic materials (MOMs), an emerging class of porous materials consisting of metal-organic frameworks (MOFs) and metal-organic polyhedra (MOPs). However, there are areas in MOM synthesis in which such self-assembly has not been fully utilized, such as controlling the interior of MOM crystals. Here we demonstrate sequential self-assembly strategy for synthesizing various forms of MOM crystals, including double-shell hollow MOMs, based on single-crystal to single-crystal transformation from MOP to MOF. Moreover, this synthetic strategy also yields other forms, such as solid, core-shell, double and triple matryoshka, and single-shell hollow MOMs, thereby exhibiting form evolution in MOMs. We anticipate that this synthetic approach might open up a new direction for the development of diverse forms in MOMs, with highly advanced areas such as sequential drug delivery/release and heterogeneous cascade catalysis targeted in the foreseeable future.
authors.affiliation: Department of Chemistry, Ulsan National Institute of Science and Technology, Ulsan 44919, Republic of Korea.
authors.forename: Jiyoung
authors.initials: J
authors.lastname: Lee
authors.affiliation: Department of Chemical Engineering, Ulsan National Institute of Science and Technology, Ulsan 44919, Republic of Korea.
authors.forename: Ja Hun
authors.initials: JH
authors.lastname: Kwak
authors.affiliation: Department of Chemistry, Ulsan National Institute of Science and Technology, Ulsan 44919, Republic of Korea.
authors.forename: Wonyoung
authors.initials: W
authors.lastname: Choe