Molybdenum Trioxide Supercapacitor Materials Preparation And Electrochemical Performance

Along with the continuously reducing of the fossil fuel storage,shortage of resources has become a global problem urgently to be solved.And environmental issues have been paid more and more attention.Green energy research and development is in full swing.Supercapacitor is a kind of electrochemical energy storage device,which is a new type of green energy storage device.Molybdenum-based oxides,carbides and sulfides have unique layered structures,which can be used as electrode materials for supercapacitors.Molybdenum trioxide electrode shows the pseudocapacitance characteristics of ruthenium oxide electrode in aqueous solution,and has the potential of supercapacitor electrode materials.In this paper,molybdenum trioxide was taken as the main research object.Molybdenum trioxide with different structures were prepared and composited with carbon materials,then the characteristics and electrochemical performance of some samples were discussed as supercapacitor electrodes.XRD,SEM,FTIR,CV,GCD and other methods were used to characterize the material phase,morphology and electrochemical properties.The main points are as follows:(1)Lamellar molybdenum trioxide was prepared by temperature control method using ammonium molybdate as molybdenum source.The particle diameter is about 2.5μm,with high crystallinity and high purity.Electrochemical performance studies show that it is a typical pseudocapacitance with a specific capacitance of 171F/g at a scanning rate of 5m V /s.(2)By controlling the acidity coefficient in the hydrothermal synthetic,the nanoscale molybdenum trioxide with one-dimensional preferred growth was prepared.The specific capacitance of the nanoscale molybdenum trioxide was higher than that of the lamellar molybdenum trioxide at 223F/g.(3)The influence of acidity coefficient on the phase structure and microstructure of the product was analyzed in hydrothermal process.With the increase of acidity coefficient,the product changes from hexagonal phase to orthogonality phase,and the micromorphology also changes regularly.When the acidity coefficient was greater than 6 the growth of hexagonal molybdenum trioxide was inhibited,and when the acidity coefficient was greater than 9 the product was pure molybdenum trioxide of orthogonality phase.(4)Molybdenum trioxide and graphene oxide were composited by hydrothermal method.The specific capacitance of the composite material was 268 F/g,and other properties were also improved.