Preparation Of Fe₃O₄ And Alloy Co_x/Ni_x-Fe_1-x@C?x=0?1? Multi-functional Nanostructured Materials With The Help Of Orange Peel

Electrochemical water splitting is regarded as a kind of technology to produce hydrogen with high purity.Water splitting has the two half-reactions,which oxygen evolution reaction?OER?and hydrogen evolution reaction?HER?,respectively.At present,Pt and RuO₂,IrO₂ noble-metal catalysts have been acted as the most outstanding catalysts.Nevertheless,the high price and scarce resources severely limit their large-scale application.Transition metal compounds were studied to replace noble metal catalysts has attracted much attention of most researchers.In this work,a series of Fe₃O₄ nanomaterials were successfully prepared via friendly dipping/adsorbing-calcining two-steps technique by using OP as carbon resource,template and reductive agent in a certain sense and Fe?NO₃?₃·9H₂O as Fe source.In the N₂,single metal Fe nanoparticles,FeCo alloy and FeNi alloy were prepared.The main research contents are as follows:?1?A series of Fe₃O₄ nanomaterials were successfully prepared by a facile dipping/adsorbing-calcining two-steps method by using OP as C-resource,and Fe?NO₃?₃·9H₂O as a single Fe source.Meanwhile,the effect of calcination temperature and amount of OP on the magnetic property and OER property of the samples was investigated.Samples characterized by X-ray diffraction?XRD?,scanning electron microscope?SEM?,transmission electron microscopy?TEM?,BET analysis and fourier transform infrared?FT-IR?spectroscopy.The results display that the coral-like Fe₃O₄ nanomaterials were successfully synthesized.OP is substantially carbonized into a carbon material in the process of calcining,facilitating the transformation of partial Fe³⁺ions to Fe²⁺and thus ensure the formation of Fe₃O₄ during the second-step of calcining process.The results indicate that OP is not only a template,but also a reductant.The special morphology and porous structure of the sample can offer many electrocatalytic activity sites for improving electrocatalytic OER performance.Moreover,samples have outstanding magnetism.?2?The second part is under the optimal preparation condition of the first part,a series of Fe@C nanoparticles were prepared by changing the calcining atmosphere to N₂ under a tubular furnace,and the samples contained a large amount of carbon.At the same time,the effect of calcination temperature and amount of OP on the magnetic property,adsorption performance,OER and HER property of the samples was investigated.The results indicate that samples with special morphology and porous structure,the edge of the samples have crimp phenomenon,these factors are conducive to electrocatalytic oxygen evolution,hydrogen evolution and adsorption.It can be known from the electrocatalytic data,outstanding OER and HER catalytic property of the sample Fe@C-800-2.0,overpotential of 378 mV and 217 mV at a current density of 10 mA cm^-2,respectively.In addition,the sample has excellent adsorption property to 50 mg L^-1MB.The preparation conditions with the best adsorption performance are calcination temperature of 700?and OP amount of 3.0000 g.?3?On the basis of the second part,FeCo alloy and FeNi alloy were prepared by adding Co/Ni and other preparation conditions were the same as before.Moreover,the addition ratio of Co and Fe is different,and the cell of samples will have corresponding changes.At the same time,when the addition ratio of Ni and Fe is changed,the diffraction peaks of the sample's XRD characteristics will also be offset accordingly.The prepared sample has a special morphology and is superimposed by many layers with porous structure and edge curl,which can offer many electrocatalytic activity sites.Moreover,the larger surface area and pore volume can induce more exposed active sites for efficient adsorption and activation of more water molecules and allow the transportion electron,and release O₂/H₂.