Preparation Technology And Properties Of Matal Catalysts For 3D Printing

Faced with the problems of expensive traditional metal printing equipment and printing consumables,limited by metal materials and high production cost,a three-dimensional printing scheme of metal paste is proposed.The equipment has many advantages,such as simple structure,low cost and no heating.In addition,nickel powder was used as printing material to prepare porous catalysts instead of platinum.Compared with commercial nickel foam,the current density during water electrolysis was higher,which made a new breakthrough in the process of preparing high-performance electrolysis water catalyst.This topic USES paste 3D printing technology to prepare metal catalyst,which reduces the cost of printing equipment and expands the selectivity of materials.Nickel and nickel alloy powder were used as experimental materials and polyvinyl alcohol(PVA)aqueous solution was used as binder.The preparation technology of porous metal Nickel catalyst was studied by 3D printing technology,including the preparation of porous metal,the influence of degreasing and sintering on porosity.Different preparation methods and properties of alloy catalysts for hydrogen production by electrolysis of water were explored.The details are as follows:1.In this paper,the improved 3D printer in the laboratory was selected as the experimental equipment,and the metal paste of nickel and nickel alloy powder mixed with PVA solution with a mass fraction of 10%was used as the printing material.By testing the properties of metal powder and PVA solution,it is concluded that when the mass ratio of nickel powder to PVA solution is 15:2,the density of paste is 3.7214g/cm3 and the viscosity is 1265pa.s.The metal paste can be extruded continuously and the relationship between extrusion pressure and extrusion speed is obtained.2.After the binder was tested by TG-DSC,the degreasing process parameters of the blank body were set and optimized,and the degreasing time was short.The influence of several heating rates on the quality of sintered products was investigated,and it was concluded that 5?/min was appropriate.In addition,the reason why the sintered green body is easy to be oxidized in high temperature environment is found,that is,before degreasing and sintering,the empty space in the furnace must be vacuumed to eliminate it.3.The contact surface of metal and the morphology of metal particles can be changed by changing the sintering temperature.This has an important effect on the tensile strength,density and shrinkage of sintered metal products.The relationship between the sintering temperature set and the quality of 3D printed products was explored.The results show that the tensile strength,density and shrinkage of metal products increase with the increase of sintering temperature.4.The properties of nickel catalyst prepared by powder sintering are better than that of commercial nickel foam.Among them,the porous nickel prepared by 3D printing is the best,and its current density is about 74.17mA/cm2,which is 7 times that of foamy nickel.This indicates that the porous nickel catalyst prepared by 3D printing has great advantages in electrolysis of water to produce hydrogen.Copper powder was added into nickel powder to form alloy powder and 3D printing technology was used to prepare porous catalyst.