Two polymolybdate-based complexes and their graphene composites with visible-light photo-responses

Two polymolybdate-based complexes with different band gaps show different visible-light photo-responses, and their graphene composite materials possess improved electrocatalytic activities for HER.

A polyoxometalate-based complex with visible-light photochromism as the electrocatalyst for generating hydrogen from water

A polyoxometalate-based complex can act as the electrocatalyst for the H₂ evolution reaction (HER) and the HER current is enhanced with visible-light irradiation.

Two Interesting One-Dimensional Chainlike Architectures Formed by Substituted Keggin Polyoxoanions and Novel Cobalt - Ethylenediamine Complexes

Two novel supported heteropolytungstates, NaH3[CoIII(en)2(OH)SiW11CoIIO39]·9.25H2O 1 (en = ethylenediamine) and [Co(en)2]4[Co4(Hen)2Si2W18O68]·H2en·6H2O 2 have been synthesized and characterized by single-crystal X-ray diffraction, electrochemistry, IR, and thermogravimetry. Compound 1 exhibits an interesting one-dimensional chainlike architecture assembled by bridged sodium ions that support monosubstituted Keggin polyoxoanions. To our knowledge, it represents the first example of a supported structure that consists of monosubstituted Keggin polyoxoanions and a novel interbridged, dinuclear Co metal unit. Compound 2 is constructed from trivacant Keggin polyanions linked through a tetrameric cobalt unit, which coordinates with organonitrogen ligands. Moreover, the sandwich-type polyoxoanions were connected by two [Co(en)2] coordination complexes, respectively, and linked by Co2+ ions into a straight chain.

Syntheses and Structures of Organic−Inorganic Hybrid Compounds Based on Metal−Fluconazole Coordination Polymers and the β-Mo8O26 Anion

Five organic-inorganic hybrid compounds, namely, [Co2(fcz)4(H2O)4][beta-Mo8O26].5H2O (1), [Ni2(fcz)4(H2O)4][beta-Mo8O26].5H2O (2), [Zn2(fcz)4(beta-Mo8O26)].4H2O (3), [Cu2(fcz)4(beta-Mo8O26)].4H2O (4), and [Ag4(fcz)4(beta-Mo8O26)] (5), where fcz is fluconazole [2-(2,4-difluorophenyl)-1,3-di(1H-1,2,4-triazol-1-yl)propan-2-ol], were synthesized under hydrothermal conditions, and crystal structures of 1-5 have been determined by X-ray diffraction. In compounds 1 and 2, metal cations are linked by fluconazole ligands to form hinged chain structures and [beta-Mo8O26]4- anions act as counterions. In compound 3, Zn(II) cations are bridged by fluconazole ligands to form 2D (4,4) networks, and each pair of these networks is linked by [beta-Mo8O26]4- anions to form a sandwich double-layer structure. In compound 4, Cu(II) cations are bridged by fluconazole ligands to form 2D (4,4) networks, and these networks are connected by [beta-Mo8O26]4- anions to form a 3D framework. In compound 5, AgI cations and [Ag2]2+ units are bridged by fluconazole ligands to form 2D Ag-fcz layers, and these layers are further connected by [beta-Mo8O26]4- anions to form a complicated 3D structure with the topology of (7(2).8(1))2(7(3).8(3))(7(2).8(11).10(1).12(1))2. Thermogravimetric analyses for these compounds are also discussed in detail. The complexes exhibit antitumor activity in vitro, as shown by MTT experiments.

Chelated heteroatoms in polyoxometalates and the topological equivalence of {Coiii(en)} to type II cis-dioxometal centers. Synthesis and structure of [{Co(en)(µ-OH)2Co(en)}{PW10O37Co(en)}2]8– and [K⊂{Co(en)WO4}{WO(H2O)}(PW9O34)2]12–

The first examples of polyoxometalate structures that incorporate embedded chelated heteroatoms point to new possibilities for stereochemical control of applications.