Design, Synthesis And Studies Of Cobalt, Copper And Molybdenum Complexes With Electrocatalytic Or Photo-catalytic Water Splitting Properties

Now, the usage of chemical fuels is increasing, the demand of energy is great, however, global storage escalate, new energy is introduced and used. Hydrogen energy enters into people’s view, which is the ideal energy in 21 th.Water splitting is composed of water oxidation and reduction. On the face, this is the simple reaction, but from the point of view thermodynamics, water splitting is not simple. Water is very stable, it demands 113.38 kcal/mol(4.92 e V) energy to make the bond breakage. Electrolysis of water can produce pure hydrogen and oxygen, but power consumption is great. According to literatures, catalyst can reduce the energy barrier, which can make water splitting, so exploring the efficient catalyst that can reduce the energy barrier, but power consumption is also great. The usage of photochemical way to evolve hydrogen is taken into consideration, and then the power consumption is reducing.In nature, microorganism can satisfy their needs by hydrogenase to catalyse water splitting for hydrogen evolution under the photosynthesis, but the biological environment is not simulated. Then, this revelation urge the scientists to study the molecular catalysts, this work look for the new catalysts of water splitting by designing new ligands and assembling different types of transition metal complexes.This paper including:First, four organic ligands were synthesized: 1-[(2-methoxy)benzene]-3-[2-(chloro) benzene]triazene(HLa), 1-[(2-carboxyethyl)benzene]-3-[benzothiazole]triazene(HLb), N,N’-bis(o-hydroxyacetophenone)ethylenediamine(H2Lc), and N,N-dimethylethylenediamino-N,N-bis(2,4-dimethylphenol)(H2Ld).Second, six new complexes were prepared and characterized: complex [CuI2(La)2] 1, complex [CuI3(Lb)(Lb’)2] 2, complex [Cu2(Lc)Cl2] 3, complex [Cu(oxpn)Cu(OH)2] 4, complex [LdMo(O)2] 5 and complex [LdCo Cl] 6, and properties of complexes were characterized by X-ray crystallography and Uv-vis and so on.Third, one new complex was studied with electric water reduction and oxidation: complex [Cu(oxpn)Cu(OH)2] 4 processed both water reduction and oxidation, TOF is 1053 h-1(p H 7.0) of hydrogen evolution, TOF is 6.7 s-1(p H 10.1) of oxygen evolution.Forth, one new complex was studied with elctrocatalytic and photo-catalytic properties: complex [LdCo Cl] 6 processed both elctrocatalytic and photo-catalytic properties, TOF is 2746 h-1(pH 7.0) of electrocatalyst, TON is 12232 of photocatalyst.Fifth, primary studies of catalytic mechanisms were proposed.