Fabrication Of Transition Metal Organic Framework Materials And Their Electrochemical Properties

Energy promotes development.Energy sources are currently dominated by non-renewable fossil energy sources,and with the strong rise of new and renewable energy sources in recent years,hydrogen energy plays a role.The catalytic decomposition of water to produce hydrogen is not only non-polluting but also produces a large amount of hydrogen,but catalysts are subject to a number of limitations.Therefore,it is of transcendental importance to develop electrocatalysts with high performance and low cost that can be used on a large scale for efficient decomposition of water to produce hydrogen.Metal-organic framework（MOF）materials have been used in the field of catalysis due to their large surface area,controllable pores and structure.And transition metal organic framework materials are considered to be non-precious metal-based electrocatalysts withapplication potential.Based on the above arguments,in this thesis,（1）four kinds of single crystal MOF has been synthesized by hydrothermal method with transition metal salt,pyridine-2,6-dicarboxylic acid,and Py₂TTz.Their electrochemical performance have been studied.The results show that MOF-Cu has the best hydrogen evolution reaction（HER）performance:overpotential（?）=196.3 m V at a current density of 0.6 m A·cm^-2,and MOF-Co has the best OER performance among the single-crystal materials with a overpotential（?）=166.3 m V at0.6 m A·cm^-2;This is mainly due to that MOF-Co has small charge transfer resistance and large double layer capacitance.（2）The cationic surfactant cetyltrimethyl ammonium bromide（CTAB）,anionic surfactant sodium dodecyl benzene sulfonate（SDBC）and neutral surfactant polyethylene glycol（PEG2000,PEG10000）have been used to regulate the morphology and electrochemical properties of MOF-Cu and MOF-Ni.The results show that the HER and OER properties of the two kinds of MOF materials are greatly improved after adding PEG10000,and the overpotentials of MOF-Cu and MOF-Ni in the HER increase from 100m V in single crystals to 60 m V when passing a current density of 1 m A·cm^-2,while the overpotential increases from undetectable to 168 m V at a current density of 10 m A·cm^-2 in the OER.In addition,the prepared MOF electrocatalysts all have good stability.