Preparation Of Porous SPE Membrane Electrode And Its Regulation Of Cyclohexene Hydrogenation

In today's society,the economy is developing rapidly,but the limited resources of the earth and the environmental problems arising from its use have become the focus of human attention.Hydrogen,as a carrier of renewable energy,has attracted attention with the advantages of high combustion calorific value,high cleanliness and abundant raw materials,and is expected to replace fossil fuels.Currently,the high growth demand for energy storage strategies promotes the development of energy storage devices with safe,low cost and long life,among which the recyclable organic hydride based hydrogen storage method has the excellent performance of energy saving and consumption reduction.Combining solid polymer electrolyte electrolysis of water with liquid unsaturated organic hydrogenation is a new approach to achieve the integration of hydrogen production and storage,which has the advantages of low cost and high efficiency.It has been shown that the addition of 3d transition metal element Ni to Pt-based catalysts to prepare binary alloy catalysts has better catalytic effect,and Ni as an alloy element is used as a catalyst for hydrogenation reaction because of its cheap,high abundance,corrosion resistance,high electrical conductivity,moderate adsorption of unsaturated organics,and the synergistic effect between Ni and Pt can both reduce the Pt consumption and enhance the resistance to CO neutrality and electrical catalytic activity.In this paper,Pt Ni/C alloy catalysts were prepared by ion beam sputtering technique,and the pore type Pt Ni/C alloy catalysts were obtained by electrochemical de-alloying post-treatment(process factors: etching solution type,etching concentration,etching time and etching temperature)of Pt Ni/C alloy catalysts.The pore-type Pt Ni/C alloy catalyst was hot-pressed with Nafion membrane to produce a pore-type SPE membrane electrode,which was applied to cyclohexene hydrogenation process,and the catalytic activity of the membrane electrode on cyclohexene hydrogenation was analyzed by detecting the hydrogenation products.The catalytic activity of the Pt Ni/C alloy catalysts was characterized by cyclic voltammetry,linear scanning voltammetry and current time methods,and the inductively coupled plasma emission spectroscopy,X-ray diffraction,scanning electron microscopy,X-ray photoelectron spectroscopy and field emission high-resolution transmission electron microscopy were used to test the crystal plane state,phase composition,bonding energy and elemental valence,surface morphology and microregion lattice phase of the pore-type Pt Ni/C alloy catalysts.The hydrogenation products of cyclohexene were tested by gas chromatography to characterize the catalytic performance of SPE-Pt Ni/C in the hydrogenation of liquid unsaturated organics.The results showed that:(1)Electrochemical analysis shows that the best post-treatment conditions in the HCl system are the corrosion solution concentration 0.5mol/L,the corrosion time 0.5h,and the corrosion solution temperature of 40?.The hydrogen evolution performance is the most significant;the best in the H2SO4 system The post-treatment conditions are that the concentration of the etching solution is 0.2mol/L,the etching time is 0.5h,and the temperature of the etching solution is 40 ?.The hydrogen evolution performance is the most significant;the best post-treatment conditions in the HCl O4 system are the concentration of the etching solution 0.7mol/L and the etching time 1.5h.The hydrogen evolution performance of the etching solution at 50? is the most significant;the best post-treatment conditions in the HBr system are the etching solution concentration of 0.2mol/L,the corrosion time of 0.5h,and the etching solution temperature of 40?.The hydrogen evolution performance is the most significant;The best post-treatment conditions in the system are that the concentration of the etching solution is 0.05mol/L,the etching time is 0.25 h,and the temperature of the etching solution is 35?.The hydrogen evolution performance is the most significant.(2)In terms of crystal plane state,phase composition,bond energy and element valence,surface morphology,and micro-domain lattice equality,comparative analysis of the electrochemical dealloying post-treatment optimization process on the original Pt Ni/C alloy catalyst It is found that the diffraction peak of the porous Pt Ni/C alloy catalyst obtained by the preferred process has a large angle shift of 0.08?0.33° relative to the original,the binding energy is reduced by about 0.28?0.51 e V,and the interplanar spacing appears about 0.9 %?2.76% reduction,which is due to the large amount of corrosion of Ni atoms during the electrochemical dealloying post-treatment process,resulting in many zero-dimensional defects on the surface of the catalyst,which causes the Pt lattice to be compressed,thereby significantly enhancing its catalysis performance.(3)The CV curve of the cyclohexene hydrogenation process shows that when the hydrogenation potential is-0.5V,the DC voltage is 1.6V,the hydrogenation temperature is 75°C,and the electrolytic hydrogen reaction temperature is 50°C,the gas chromatography and Tafel curves all prove that the porous SPE membrane electrode exhibits enhanced cyclohexane conversion rate and current efficiency.