| As the world economy developing rapidiliy and the rapid increase of the demand for energy,the development of clean,sustainable and efficient energy has become one of the primary tasks of researchers.In addition,as people pay more and more attention to renewable energy,the research on finding better energy conversion technology and developing renewable energy at a faster speed has also been promoted.At present,the core of the conversion technology is to find suitable and sensitive electrocatalytic materials.Compared with previous noble metals,metal organic framework materials(MOFs)are widely used because of their unique structural characteristics,simple synthesis process and stable catalytic performance.Therefore,in order to find the electrocatalytic materials with high cost performance and excellent performance,we synthesized the metal organic framework materials with two-dimensional ultra-thin structure,high activity and stable performance as the electrocatalysts,and on this basis,we carried out a series of tests on the electrochemical performance of biocatalytic organic small molecules and their applications in supercapacitors.The research mainly includes the following aspects:(1)Preparation of Co MOF with two dimensional sheet structure and its application in glucose electrocatalysisCo-MOF(Co2(OH)2 PTA)was prepared by one-step solvothermal method with DMF/C2H5OH as solvent and terephthalic acid as carrier.It is found that due to the different input ratio of raw materials,the synthesized Co MOFs have two kinds of structures,one is shell like multilayer,the other is ultrathin 2D nanosheets,but the elements and functional groups of the two kinds of Co MOFs are the same material.Compared with shell like multi-layer co MOF,ultra-thin two-dimensional(2D)nanosheets(about 2.041 nm in thickness)have higher stability,higher sensitivity(219.67μA mM-1cm-2),better activity,and excellent selectivity for glucose in alkaline electrolyte,low detection limit of 0.25μM(signal-to-noise ratio S/N=3),The linear calibration range is wider(0.5-8065.5μM),which is more suitable for the electrode material of electrocatalytic glucose oxidation reaction(GOR).(2)Preparation of Ni MOF with two-dimensional sheet structure and its application in ascorbic acid electrocatalysisUltrathin nanosheet Ni-MOF assembly[Ni3(OH)2(C8H4O4)2(H2O)4]·2H2O was synthesized by a simple solvothermal method using DMF/NaOH as solvent and terephthalic acid as carrier.In order to explore the suitable electrocatalyst,three groups of samples were taken from the thermal reaction for 4h,8h and 12h,and the electrocatalytic performance of ascorbic acid(AA)was tested in PBS(pH=7.2).Electrochemical data analysis showed that AA oxidation reaction had good catalytic activity and stability,linear calibration range(0.5μM-8065.5μM),good detection limit(0.25μM).The reason may be related to the structure of ultrathin nanosheets.This structure not only provides a way to improve the electrocatalytic performance,but also makes it more stable in the electrocatalytic AA due to its special aggregation state.(3)Preparation of hollow structure NiCoFeLDH@ZIF-67 and its electrochemical applicationA simple synthesis method was used to prepare ZIF-67 materials with hollow structure by doping nickel and iron ions and controlling the etching time NiCoFeLDH@ZIF-67.And its electrochemical performance was tested in supercapacitor.The electrochemical performance of the hollow structure NiCoFeLDH@ZIF-67 is expressed that the capacitance and redox reaction kinetics of the electrode were obviously optimized,indicating its excellent electrochemical performance.It has a high specific capacitance of 1202.08 F g-1 at a current density of 5 A g-1 which shows its high power characteristics.Especially for the hollow structure NiCoFeLDH@ZIF-67)the coincidence material has good cycle stability,better capacitance reversibility and larger capacitance,which improves the cycle life of the electrode.So,It is a very excellent electrode material for supercapacitors. |
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