Study On The Relationship Between Dispersibility/Stability Of Metal Chalcogenide Supertetrahedral Clusters And Their Packing Mode In Crystal Lattice

Crystalline materials composed of metal chalcogenide supertetrahedral clusters with precise structure,multi-metal,porous and semiconducting properties hold great application potentials in photocatalysis,ion exchange,gas adsorption,and so on.Among them,The isolated supertetrahedral cluster-based crystalline materials and 3D framework materials based on four-connected supertetrahedral clusters are playing an increasingly important role in the field of catalysis and host-guest chemistry.Such applications depend on the dispersibility of the isolated clusters in medium and the stability of cluster-based framework,respectively.However,studies on the dispersibility of clusters and the stability of clusters-based framework materials still remain insufficient up to date.Until now,although a few examples of isolated clusters have been reported,the realization of dispersibility mainly depends on the regulation of polarity of mixed organic solvents,and the dispersible amount is really low,which seriously restricts the performance study of discrete clusters.Therefore,it is of great significance to synthesize the discrete cluster-based crystalline chalcogenide materials that are highly dispersible and independent of solvent polarity.In addition,the issue of the stability of cluster-based chalcogenide framework materials is still urgent problem and need to be addressed in the study of host-guest chemistry of chalcogenide semiconductors.Exploring the correlation between packing mode of clusters in the three dimensional chalcogenide framework and the overall structural stability attaches great importance to the subsequent synthesis and performance development of chalcogenide framework materials.In this thesis,supertetrahedral cluster-based OD and 3D crystalline chalcogenide materials were synthesized via solvothermal methods,and also the influences of packing modes of clusters on the dispersibility of OD crystalline chalcogenide materials and the influences of cluster vertex coordination mode on the stability of 3D crystalline chalcogenide framework materials are discussed.The specific works are summarized as follows:1.The synthesis,dispersibility and photoelectric properties of isolated supertetrahedral T4 nanoclusters with loose packing modeThree isostructural chalcogenides materials composed of the same type of isolated T4-MInS(M=Mn/Zn/Fe)nanoclusters were synthesized by solvothermal conditions.Such nanoclusters adopt loosely sodalite-net packing mode and display superior dispersibility to other cases with close packing mode.The photoelectric experiments show that T4-ZnInS has excellent photodegradation performance for Rhodamine B due to its high specific surface area and suitable band structure.This work provides a guidance on dispersibility and its optoelectronics of isolated clusters.2.Stable supersupertetrahedron with infinite orders via the assembly of supertetrahedral T4-ZnInS clustersWith the support of 3,5-dimethylpiperidine and pyrrolidine,a new family member of Tp,q-based hierarchical metal chalcogenide architecture was synthesised under solothermal conditions.The structure was created by assembling regular T4-ZnInS clusters into a periodically "hollowed-out" cubic ZnS-type structure framework(T4,∞)via the cross-linker of the tetracoordinated vertex μ4-S2-.Ion-exchange and CO2 adsorption experinents suggest that such a structure with a vertex μ4-S2-linker has structural stability superior to those of previously reported chalcogenide open frameworks composed of the same T4-ZnInS clusters with a bicooruinated(μ2-S2-)or a tricoordinated(μ3-S2-)cross-linker.This work gives a theoretical support for the study of cluster-based porous chalcogenide materials with stable frameworks,and provides a synthesis basis for the study of host-guest chemistry of semiconductor materials.In this thesis,the influences of packing modes of isolated supertetrahedral nanoclusters on the dispersibility were studied.At the same time,the effects of coordination modes of vertex chalcogenide atoms on the stability of 3D crystalline chalcogenide framework materials were systematically explored.This work provides a significant theoretical guidance to the synthesis and properties of supertetrahedral cluster-based crystalline chalcogenide materials.