| Nowadays,many carbon-based materials,such as coal,natural gas,oil and other unsustainable resources are increasingly consumed.Energy demand and environmental pollution encourage researchers to seek alternative energy and energy storage devices.Hydrogen energy is more promising renewable energy.The way of hydrogen production in industry mainly includes electrolytic water,coal gasification,catalytic conversion of heavy oil and natural gas.Among them,electrolytic water is an important way to produce hydrogen,and its core reaction is oxygen evolution and hydrogen evolution.Oxygen evolution reaction which is a slow kinetic reaction,highly depend on solution pH.Therefore,the development of economical and efficient oxygen evolution reaction catalysts is of great significance for improving the efficiency of hydrogen production and its application in related fields of fuel cells and energy storage.The content of this paper is focused on the characteristics and current researches of oxygen evolution reaction.Nanounits of controllable morphology and composition grow in situ on the surface of nickel foam and copper foam to build electrode materials with high mechanical strength and activity.Study the effects of composition and structure on the oxygen evolution reaction performance and application in the electrocatalytic oxidation of biomass platform molecules.It provides new ideas and methods to design high efficiency electrocatalytic materials.Two parts include in this paper.1.The nickel-aluminum hydrotalcite precursor grow in situ on the nickel foam surface by a hydrothermal method.With ion exchange method,anions containing B or P elements are introduced into the hydrotalcite layer.Then,through high-temperature reduction treatment,highly dispersed nickel boride and nickel phosphide with three-dimensional hierarchically structure are obtained,which are represented as NiB-Al2O3/NF and NiP-Al2O3/NF,respectively.It was applied to the electrocatalytic oxygen evolution reaction of water and the selective electrocatalytic oxidation of 5-hydroxymethylfurfural.When the current density reached 10 mA·cm-2,the oxygen evolution reaction overpotentials were respectively 221 mV and 193 mV,the conversion of HMF and selectivity were 99.0%and 98.0%,respectively.The results show that B and P elements can regulate the electronic state of metal Ni and thus affect the catalytic performance.The resulting electrode materials exhibit good chemical stability.2.The copper foam provide the copper source and conductive substrate,With the solution of sodium hydroxide and ammonium persulfate as oxidant,copper hydroxide nanowires precursor grow in-situ perpendicular to the skeleton structure surface of copper foam.The Cu(OH)2 was roasted into CuO nanowires in high temperature,and then nickel cobalt hydrotalcite coated on the surface of CuO nanowires in shell by electrodeposition.Through SEM,TEM and other means,that the morphology characterization of shell morphology and thickness of the electrode materials of CuO@NiCo(OH)x core-shell structure would be obtained.The CuO@NiCo(OH)x electrode material,with the excellent conductive of copper-based materials as well as electrical properties of hydrotalcite materials,could provide large electrochemical specific surface area,is conducive to improve the OER electrocatalytic efficiency.The result shows,OER under alkaline conditions has the prominent performance.When the current density reaches 10 mA·cm-2,the overpotential was about 302 mV,the Tafel slope used to measure the dynamic process is 93 mV·dec-1.In the case of long-term charged with electricity,the potential remained stable. |
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