Preparation Of Gold / Metal Oxide Composites And Study On Their Electrocatalytic Performance For Oxygen Precipitation

Splitting water into hydrogen and oxygen via electrocatalytic or photocatalytic routes has been considered as a feasible way to store renewable energy (such as wind and solar energies). Oxygen evolution reaction(OER) has been considered as the bottleneck step in water electrolysis to simultaneously produce hydrogen and oxygen. At present, the commonly used OER are precious metal oxides, such as PtO2, IrO2, RuO2. Because of its expensive, less reserves, not large-scale production applications. Therefore, seeking efficient and low cost of OER is the way to solve the problem. Recent studies have found that abundant transition metal oxides (such as manganese oxides, nickel oxide, nickel hydroxide) and precious metals Au, Pt, Pd complexes can increase its electro-catalytic activity, not only reduces costs, but also improves the performance of catalytic material. So it become the research hot spot.In this article, preparing Au/C/Mn3O4, AuRNs/C/Mn3O4, Au/m-Ni(OH)2 composite materias via compositing noble metal gold, the conductive polymer and transition metal oxide. Transmission electron microscopy(TEM), X-ray photoelectron spectroscopy(XPS), X-ray diffraction(XRD), High resolution transmission electron microscopy(HR-TEM) were employed to characterize the products. The nanocomposites with monodisperse nanostructure are expected to be synthesized by altering the synthetic conditions. The main results are as follows:(1) Based on gold nanoparticles nuclear, surfactant F127 auxiliary synthesis of Au/POMA core/shell structure composite materials. A thin layer of MnO2 is coated on surfaces of Au/POMA, under acidic conditions, KMnO4 is reduced to MnO2, this is due to the reduction of the polymer. Finally, preparation of Au/C/Mn3O4composites was roasting at different temperatures under N2. The electrochemical OER test, Au/C/Mn3O4(300℃) has good electrocatalytic activity.(2) AuRNs has been synthesized via seed growth method, on the basis of the first part, By adjusting the quantity of F127, polymer monomers, uniform morphology core-shell imaterial is prepared. A thin layer of MnO2 is coated on surfaces of AuRNs/POMA. Finally, preparation of AuRNs/C/Mn3O4 composites was roasting at different temperatures under N2. The electrochemical OER test, AuRNs/C/Mn3O4 (300℃) has good electrocatalytic activity.(3) First, Ni(OH)2 nanowires were synthesized by a modified hydrothermal method. Then the m-Ni(OH)2 nanowires were prepared through an anionexchange reaction derived from Ni(OH)2 nanowires. Au/m-Ni(OH)2 via HAuCl4 was reduced by NaBH4, Au nanoparticles evenly distributed on m-Ni(OH)2 nanowires. Au nanoparticles was stable and not easy to reunite, this was due to the interaction between Au nanoparticles and S2- in Ni(OH)2. The electrochemical OER test, the Au/m-Ni(OH)2 has good electrocatalytic activity.