Synthesis,Oxygen Evolution,chemical Energy Storage Of Transition Metal Compounds Multiple Nano-materials Order-arrays

With the rapid development of the energy crisis and the global economy,the demand for a new generation of sustainable energy is increasing.As a promising energy candidate,hydrogen has been extensively studied.Compared with the traditional hydrogen production methods,hydrogen production by electrolysis of water is a green,pollution-free and simple method.However,the slow kinetics of the oxygen evolution half-reaction is one of the main factors limiting the electrolysis of water.Therefore,it is imperative to develop an oxygen evolution catalyst with high catalytic performance.Multi-material has attracted much attention in the field of oxygen evolution catalyst,thanks to their structure diversity and electronic adjustable.In addition,electrochemical supercapacitor as a new way to solve the energy crisis,due to their higher power density,superior charge-discharge process,larger lifespan,better environment,etc.The quality of the electrode materials has a very important impact on the performance of supercapacitors.Transition metal compound multi-element materials have higher electrochemical activity and more abundant Faraday reactions.Meanwhile,the transition metal compound multi-material can store charge through an electrostatic adsorption process or through an oxidation-reduction reaction.Therefore,transition metal multi-materials have become a research hotspot in the field of electro-catalysis and electrical energy storage.Based on these,designing synthesis transition metal multi-materials in electrocatalysis and electrical energy storage which have very important theoretical significance and practical value.The information are as follows:1)One-step synthesis and high-efficiency electrocatalytic oxygen evolution performance of nickel-based bi-anionic compound nano-arrayNi-Se-S nanorods supported on nickel foams are synthesized by one-step solvothermal method.Structural characterization shows Ni-Se-S nanorods have a triangular phase structure,and forms an ordered array structure on the nickel foam substrate.Electrochemical tests shows that in the 1 mol·dm-3 KOH solution,at the current density of 50 mA·cm-2 the overpotential is only 344 mV,the Tafel slope is 33.43 mV·dec-1,and it has excellent electrochemical stability.The job is provides a new method about polyanionic compound’s synthesis,and enriches the research field of oxygen evolution in electrolyzed water.2)The electrochemical performance and application in hybrid supercapacitors based on nickel-based bi-anionic compound nano-arrayThe Ni-Se-S electrodes obtained above are used in electrochemical energy storage performance.Results reveals that Ni3(Se0.3S0.7)2 nano-array has 13.50 F·cm-2 surface capacitance,even at a current density of 5 A·g-1,the area capacitance still can reach 7.88 F·cm-2.The outstanding performance of this material is inseparable from its unique structure,good conductivity and excellent synergy among these three elements.Subsequently,liquid asymmetric supercapacitors based on Ni3(Se0.3S0.7)2 and activated carbon can attain 0.50 mWh·cm-2 areal capacitance density and outstand cycle stability.These results fully prove that the Ni3(Se0.3S0.7)2 nano-array has a good application prospect in the field of advanced energy storage equipment.3)Synthesis and electrocatalytic oxygen evolution performance based on NiSe/CoSe/Ni3Se2 nano-composite arrayHierarchical nano-array with a gladiolus-like structure is obtained via the self-template synthesis method.Structural characterization shows that the middle of the hierarchical nanoarray is a one-dimensional Ni3Se2 nanowire,and the outside is a flower-like structure formed by NiSe and CoSe nanosheets.The electrocatalytic test results show that,at a current density of 20 mA·cm-2,the overpotential only needs 336 mV.After 1000 cycles,the overpotential increase only 17 mV and the LSV curve keeps well and these showing that NiSe/CoSe/Ni3Se2 good durability.4)Electri-chemical performance with energy storage research of NiSe/CoSe/Ni3Se2 grade nano-arrayThe NiSe/CoSe/Ni3Se2 array act as the electrodes that test electrochemical performance in the three-electrode test system.Electrochemical tests exhibites a higher specific capacitance of 1666 F·g-1 at 0.5 A-g-1.After 5000 times of charging and discharging,the capacitance retention rate can reach 85.19%,which has good cycle stability.These results indicates that NiSe/CoSe/Ni3Se2 arrays are promising as electrodes for supercapacitors.