The Preparation And Property Research Of Based On Molecular Catalysts Modified Tungsten Oxide Photoanode

Direct utilization of sunlight to split water into hydrogen and oxygen is an ideal way to convert solar energy into chemical energy and to sovle the energy and environmental problems. Photocatalytic decomposition of water to produce hydrogen reaction system, and it includes two reactions of water oxidation and hydrogen reduction. Among them, water oxidation reaction provide the necessary protons and electrons for producing hydrogen or carbon dioxide reduction, which is the foundation of the realization of solar energy conversion. Therefore, it is the core of the artificial photosynthesis system to build a stable and efficient photocatalytic decomposition water device.Iridium catalyst with stable structure of molecular level [(L2bpy)IrⅢCp*-(Cl)]+(L=-PO3H2 or -COOH, bpy= 2,2’-bipyridine, Cp*= pentameth-ylcyclopentadienyl) modefied inorganic semiconductor material tungsten trioxide to establish inorganic semiconductor/ molecular catalyst composite light anode (FTO/WO3/Ir-PO3H2). The performance test results showed that the catalytic activity of the composite electrode was significantly increased than that of the WO3 anode under acidic conditions or in the neutral condition. In the potassium nitrate aqueous solution of pH= 1.0, under the external bias potential 1.23 V vs. RHE. The photocurrent density of FTO/WO3/Ir-PO3H2 photoanode can reach 1.2 mA/cm2, than current density of the thin iridium oxide modfied the WO3 anodic increase more than doubled. And it still be able to maintain a certain photocatalytic activity after light 1800s.Electroplating a layer of titanium oxide film in the inorganic semiconductor/molecular catalyst composite electrode surface to construct a new type of FTO/WO3/Ir/TiOx compound photoanode. Photoelectricity test results showed that the electrodeposition of titanium oxide composite electrode FTO/WO3/Ir-COOH/TiOx than FTO/WO3/Ir-COOH electrode water oxidation performance improved by 40%.In addition, n-type rod WO3 nano material was prepared by hydrothermal method. Loading the molecular iridium catalyst to the WO3 electrode respectively used PMMA polymer and covalent bond adsorption two ways to form a composite photoanode. Under the visible light irradiation, the two ways to prepare the composite electrodes were significantly improved than the WO3 electrode in the catalytic oxidation of water.