Chang Seop Hong

Facile postsynthetic oxidation of the thiol-laced UiO-66-type framework UiO-66(SH)2 enabled the generation of UiO-66(SO3 H)2 with sulfonic acid groups covalently linked to the backbone of the system. The oxidized material exhibited a superprotonic conductivity of 8.4×10(-2) S cm(-1) at 80 °C and 90 % relative humidity, and long-term stability of the conductivity was observed. This level of conductivity exceeds that of any proton-conducting MOF reported to date and is equivalent to the conductivi

A framework en-Mg2(dobpdc) (1-en; en = ethylenediamine) functionalized with the primary amine en was prepared via postmodification. From synchrotron PXRD data, it is revealed that the cell parameters change upon grafting of en and CO2 uptake. The adsorbed CO2 amount of 1-en is 4.57 mmol g−1 (16.7 wt%) at 25 °C and 1 bar and decreases to 3.00 mmol g−1 (11.7 wt%) at 150 °C. Noticeably, 1-en shows a significant CO2 uptake (3.62 mmol g−1, 13.7 wt%) at 0.15 bar, which is comparable to the CO2 partial

This review provides a comprehensive overview of post-synthetic modification of porous materials to synthesize superprotonic solid electrolytes and their membranes and explore their applications in proton exchange membrane fuel cells.

An amine-functionalized metal-organic framework (MOF), dmen-Mg₂(dobpdc) (dmen = <i>N</i>,<i>N</i>-dimethylethylenediamine), which contains a heterodiamine with both primary and tertiary amines, was prepared <i>via</i> a post-synthetic method. This material exhibits a significant selectivity factor for CO₂ over N₂ that is commensurate with top-performing MOFs. It is remarkable that the solid is fully regenerated under vacuum or flowing Ar at low desorption tempera

This review article introduces MOF-74 type variants and their CO₂ capture properties in terms of the open metal site and the functional groups on the ligand and open metal sites.

An S-shaped gas isotherm pattern displays high working capacity in pressure-swing adsorption cycle, as established for CO₂ , CH₄ , acetylene, and CO. However, to our knowledge, this type of adsorption behavior has not been revealed for NH₃ gas. Herein, we design and characterize a hydrogen-bonded organic framework (HOF) that can adsorb NH₃ uniquely in an S-shape (type IV) fashion. While conventional porous materials, mostly with type I NH₃ a

Two new one-dimensional single azide-bridged metal(II) compounds [[M(5-methylpyrazole)4(N3)]n](ClO4)n(H2O)n [M = Co (1a), Ni (2a)] were prepared by treating an M(II) ion with stoichiometric amount of sodium azide in the presence of four equivalents of the 3(5)-methylpyrazole ligand. The isostructural compounds 1a and 2a crystallize in the monoclinic space group P2(1)/n. The azide bridging ligands have a unique end-to-end coordination mode that brings two neighboring metal centers into a cis-posi

Luftdicht verschlossen: In einem Ni9W6-High-Spin-Cluster (S=12) mit Cyanidbrücken sind die NiII- (grün) und WV-Ionen (violett) ferromagnetisch gekoppelt. Die Substitution der Solvensmoleküle an der Clusteroberfläche gegen 2,2′-Bipyridin ergab einen luftstabilen Ni9W6-Einzelmolekülmagnet. Supporting information for this article is available on the WWW under http://www.wiley-vch.de/contents/jc_2001/2006/z601759_s.pdf or from the author. Please note: The publisher is not responsible for the content

NH₃, essential for producing artificial fertilizers and several military and commercial products, is being produced at a large scale to satisfy increasing demands. The inevitable leakage of NH₃ during its utilization, even in trace concentrations, poses significant environmental and health risks because of its highly toxic and reactive nature. Although numerous techniques have been developed for the removal of atmospheric NH₃, conventional NH₃ abatemen

A combined sonication and microwave irradiation procedure provides the most effective functionalization of ethylenediamine (en) and branched primary diamines of 1-methylethylenediamine (men) and 1,1-dimethylethylenediamine (den) onto the open metal sites of Mg₂ (dobpdc) (1). The CO₂ capacities of the advanced adsorbents 1-en and 1-men under simulated flue gas conditions are 19 wt % and 17.4 wt %, respectively, which are the highest values reported among amine-functionalized

Ferromagnetic coupling between metal centers and end-to-end coordination of the azido bridges were found together for the first time in the one-dimensional nickel(II) compound [{Ni(5-methylpyrazole)4(N3)}n](ClO4)n⋅n H2O (1; the structure in the unit cell is shown). The ferromagnetic coupling involving spin canting occurs between the two crystallographically distinct types of magnetic centers in 1 owing to a large Ni-N3-Ni torsion angle of 75.7° and a dihedral angle of 60.6° between two types of

Although numerous porous adsorbents have been investigated for NH₃ capture applications, these materials often exhibit insufficient NH₃ uptake, low NH₃ affinity at the ppm level, and poor chemical stability against wet NH₃ conditions. The NH₃ capture properties of M₂ (dobpdc) complexes (M=Mg²⁺ , Mn²⁺ , Co²⁺ , Ni²⁺ , and Zn²⁺ ; dobpdc^4- =4,4-dioxidobiphenyl-3,3-dicar

This highlight demonstrates a comprehensive overview of MOF-74-type frameworks in terms of synthetic approaches and pre- or post-synthetic modification approaches.

The transport and magnetic properties of single crystals of ${\mathrm{La}}_{1\ensuremath{-}x}{\mathrm{Ca}}_{x}{\mathrm{MnO}}_{3}$ $(x=0.2,$ 0.3) have been investigated. The transport and magnetization results of the ferromagnetic insulator, ${\mathrm{La}}_{0.8}{\mathrm{Ca}}_{0.2}{\mathrm{MnO}}_{3},$ are quite different from those of ${\mathrm{La}}_{0.7}{\mathrm{Ca}}_{0.3}{\mathrm{MnO}}_{3}$ that falls into a ferromagnetic metal. We have found that the paramagnetic to ferromagnetic transitions ob