| The energy competition is becoming more and more fierce in the world,and people need more and more energy to get a high-quality life.Hydrogen energy as a clean energy source,has the advantages of low environmental pollution,abundant resources,and renewable energy,and has received important attention from everyone.At present,the industrial hydrogen production method used in electrolyzed water mainly uses iron as the cathode surface and nickel as the anode surface of a series electrolytic cell?like a filter press?to electrolyze the aqueous solution of caustic potassium or caustic soda.It is costly,but the product purity is large,and it can directly produce hydrogen with a purity of more than99.7%.The two half reactions of electrolyzed water include hydrogen evolution?HER?and oxygen evolution?OER?,but the best catalysts for hydrogen evolution and oxygen evolution are commercial Pt/C and ruthenium oxide or rubidium oxide.However,the lack of resources and the high price prevent them from being widely used.In recent years,transition metal phosphides?wide source,low price,excellent performance?have stood out among many catalysts,but the low conductivity,the absence of active sites,and the stability of long-term reaction at different p H have greatly reduced their electrolysis.Therefore,it is a big challenge to design an electrolyzed water catalyst that can have high activity,good conductivity,and long stability for acid or alkaline solutions.Focusing on the above design principles,the main research contents of this article are as follows:The base material used in the second chapter of this paper is a carbon film made of fresh magnolia leaves.The unique vein structure of the carbon membrane,combined with natural pores,increases the contact area of the reaction,which is conducive to subsequent experiments.The electrochemical deposition method is simple and easy to operate.A fixed voltage is used to electrodeposit the active material on the surface of the carbon film,so that Fe-Co-P grows uniformly along the veins and holes of the carbon film,and is wrapped on the surface of the carbon film.The oxygen evolution performance of the electrolyzed water was tested.It only required an overpotential of 151 m V?standard hydrogen electrode?to reach 10 m A cm-2,and the Tafel slope was only 77.78 m V dec-1.And after 10 hours,the stability is good.The third chapter of this article still uses the carbon film made of magnolia leaves as the substrate material.Similarly,a constant potential electrochemical deposition method is used to deposit cobalt phosphide with a specific morphology on the carbon film.By changing the different phosphorus content.And test their electrochemical performance,then found that Co P-0.6/C has the best performance of electrolyzed water,and it can be used as a rare bifunctional catalyst at the same p H value.In 1 M KOH electrolyte,the HER overpotential at 10 m A cm-2 is 140 m V,the OER overpotential is 250 m V,and the potential of total dehydration is 1.72 V at 50 m A cm-2.The Tafel slopes were 109.30 m V dec-1 and137.59 m V dec-1,respectively,and after 24 hours of cycling,they also showed good catalytic performance.The base materials in Chapter four of this article have been changed from the above to use the leaves of laurel.The method of hydrothermal synthesis is to load iron hydroxy on the carbon film and then carry out sulfur phosphating to obtain Fe-S-P/C.The Fe-S-P/C on the carbon film has a unique nanorod structure,and exhibits excellent hydrogen evolution,oxygen evolution and total hydrolysis performance in 0.5 M H2SO4electrolyte.At 10 m A cm-2,the HER overpotential is 148 m V,the Tafel slope is 99.96 m V/dec,the OER overpotential is 53 m V,and the Tafel slope is 103.24 m V/dec.At 50 m A cm-2,the potential for total water dissociation is 1.92 V.After a long cycle,it has good stability. |
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