The Preparation And Photocatalytic Performance Of Fe³⁺ Substituted Magnesium Aluminate Spinel Nanoparticles

Photocatalytic technology has attracted more and more attention due to its wide application in the field of new energy exploit and environmental pollution control in recent years.Photocatalyst plays a very important role in it.As a typical representative of spinel materials,magnesium aluminate spinel has attracted extensive attention due to its characteristics of easy adjustment of composition,stability of structure and resistance to acid and alkali corrosion.It is found that magnesium aluminate spinel has certain photocatalytic properties under ultraviolet light,but its catalytic effect is not ideal.Transition metal doping is one of the effective means to improve the photocatalytic performance of materials,so in this paper,Fe³⁺is used to substitute Al³⁺to reduce the band gap of magnesium aluminate spinel and improve its photocatalytic performance.In this paper,the Mg(Fe_xAl_1-x)₂O₄ samples were synthesized via co-precipitation method and sol-gel method with the ingredient of magnesium salt,aluminum salt and iron salt,and the XRD,BET,SEM,UV-Vis DRS characterization methods were adopted to test and analysis their phase composition,pore size and distribution,surface morphology and photoelectric properties.Finally,the degradation of methylene blue solution was irradiated with mercury lamp at a certain power.The photocatalytic properties of the products obtained by different amount of Fe³⁺addition,different preparation methods and different calcination temperature were studied.The following results are obtained in this paper.?1?With NaOH as precipitant,samples were prepared successfully via co-precipitation method.It is found that when the calcination temperature is 700?,the samples with Fe³⁺addition of 5%and 10%have better photocatalytic activity.?2?With NH₃·H₂O as precipitant,samples were prepared successfully via co-precipitation method.It is found that when the calcination temperature is 700?,the samples with Fe³⁺addition of 5%,10%and 15%have better photocatalytic activity.?3?The samples were prepared successfully via sol-gel method.It is found that the samples have good photocatalytic performance at 600?.When the calcination temperature is 700?,the samples with Fe³⁺addition of 5%and 10%have better photocatalytic activity.?4?When the calcination temperature is 700?,it is found that the sample prepared by coprecipitation method with NH₃·H₂O as precipitant has better photocatalytic activity.