Syntheses And Assembly Of Multinary Germanium-sulfur Functional Compounds

Nowadays, germanium-sulfur compounds, which have unique structures and excellent properties, are becoming a research hotspot, because this kind of compounds has potential applications not only in the aspects of ion exchange, solvent induced discoloration and catalysis etc., but also in the photoelectric performance aspects of nonlinear optics, semiconductor and photoconductor.Tetrahedral building block MQ4 is the basic building unit of germanium-sulfur compounds. Through sharing edges or sharing corners, this MQ4 can form anionic framework clusters of different structures, among which the two most common clusters are dimer(Ge2Q64-) and tetramer(Ge4Q104-), and if adding transition metal ions into tetramer(Ge4Q104-), we can obtain mesoporous sulfides. The corresponding counterions of these clusters are usually the protonated organic amines and quaternary ammonium cations etc. Recently, in order to enrich the structures and properties of germanium-sulfur compounds, researchers begin to pay attention to the incorporation of transition metal complexes with their structures. Since compounds of transition metal vanadium or transition metal copper have flexible coordinated manners and diverse valences, they have been widely used in sensors, energy storage devices and catalysis. In this paper, supramolecular clusters and microporous polymers with novel structures are obtained through introducing transition metal vanadium and copper into the system of germanium-sulfur compounds. The major contents are as follows:Part 1, through introducing transition metal vanadium into chalcogenide system we got two compounds {[V(en)2]2O}Ge2S6(1)(en = ethylenediamine) and [VO(dap)2]2Ge2S6·dap(2)(dap = 1,2-diaminopropane) at a certain temperature. Compounds 1 and 2 were synthesized using a similar solvothermal procedure except using a different amine ligand. The study found that:(1) Though the two compounds were obtained under the similar synthetic conditions, the two products are completely different. Supramolecular hexagonal nano tubes for compound 2 was characterized crystallographically, while compound 1 was only a common 1-D polymer;(2) Different reduction abilities of sulfur–amine systems are demonstrated by the synthesis of compounds 1 and 2. The V(V) is reduced to V(III) in strong reduction en system and to V(IV) in weak reduction dap system. It is an unexpected result that different valence states and supramolecular structures of 1 and 2 only appear from a branched methyl group in amine.Part 2, through introducing metal copper(Cu) and Mo S42- or WS42- into the structure of germanium sulfur clusters at a certain temperature, two desired products [(CH3)4N]4[(Ge4S10)Cu4Mo2S8]·2DMF(3) and [(CH3)4N]4[(Ge4S10)Cu4W2O8]·2DMF(4) were obtain. Compound 3 was constructed by [Ge4S10]4– clusters and inorganic linear [S–Cu–Mo S4–Cu–S] pillars. It’s a(44) 2D anionic framework, the two interpenetrated 2D nets further construct a MOF-like 3D structure that is uncommon for inorganic materials. The worth noting feature of this structure is the channels formed along the c direction. Compound 3 exhibited ion-exchange properties and photocatalytic degradation of methyl orange capability.