The Assembly And Photocatalysis Properties Of Metal Organic Octahedron

Metal organic polyhedrons assembly of predesigned inorganic and organic building blocks can be used to construct well-defined, nanosized molecular cavities that can catalyze multiple chemical transformations. It has become a hot field in coordination chemistry. The inner cavities formed through the coordination between metal irons and organic ligand are inspired by the poket features of natural enzymes,in which metal irons act as the catalytic sites. Metal organic polyhedrons can act as the host to encapsulate guest moleculars just like what natural enzymes do in nature.After the encapsulating, the guest moleculars and the catalytic sites are forced close together, making the originally intermolecular electron transfer into a intramolecular electron transfer, which improve the efficiency greatly. Because the size and formselective festriction that the inner cavities provide, metal organic polyhedrons can be used in many catalytic reactions.Due to the energy crisis and environmental pollution problems in today’s society,the developing of new and clean energy becomes more and more important. Splitting water using solar energy has been a focus of great attention as a possible means for converting solar energy to chemical energy in the form of clean and renewable hydrogen fuel. The overall splitting of water makes it capable of photocatalytically producing hydrogen and oxygen at the same time, which makes many scientists pay more attention to this field. H2 S is an abundant chemical produced by industry and occurring in nature. The development of a sustainable and economically viable photochemical approach that can split H2 S into H2 and S remains a big challenge.Here, the main work of this paper includes the following two parts:1. A new metal organic octahedral(Ni6(TFT)4) was built through supramolecular assembly. Each metal center coordinates form a distorted squre-planar configuration.The three rigidly separated NS chelators of each ligand coordinate with three different metal centers, whereas six metal centers occupy the vertical positions of the octahedron. This octahedral cage can encapsulate fluorescein as the photoactive guest.Triphenylphosphine(PPh3) and its derivatives were chosen as model compounds.This supramolecular system combine the oxygen transformation and hydrogen production in a one-pot reaction using water as the source of both oxygen and hydrogen atoms.2. A new metal organic octahedral(Co6(TNP)4) was built through supramolecular assembly. The pseudo S4 symmetry is achieved by alternatively arranging the four planar ligands onto the eight triangle faces of the octahedron defined by the six metal ions. This octahedral cage can encapsulate fluorescein as the photoactive guest. This host-guest system can be used in the overall splitting of H2 S into H2 and S.