Magnetic properties and photocatalytic mechanism of magnetic separable M-type strontium ferrite photocatalyst

Abstract

M-type strontium ferrite photocatalysts were successfully synthesized by three different methods including combustion assisted sol-gel method, microwave irradiation assisted sol-gel method and conventional sol-gel method. The phase structure, surface morphology, optical properties, magnetic properties and photocatalytic activity of the M-type strontium ferrite photocatalyst are strongly dependent on the synthetic route. The effects of the irradiation time, catalyst loading, initial dye concentration and pH value on the photocatalytic activity of the M-type strontium ferrite photocatalyst have been systematically studied. The M-type strontium ferrite photocatalyst synthesized by a microwave irradiation assisted sol-gel method exhibits an excellent optical properties, magnetic properties and photocatalytic activity. The optimum irradiation time, catalyst loading, initial dye concentration and pH value of the M-type strontium ferrite photocatalyst is 180 min, 3 g l-1, 25 mg l-1 and 10, respectively. The recycle experiments show that the M-type strontium ferrite photocatalyst has good magnetic separation recovery ability. The hydroxyl radicals (•OH) play a key role for the M-type strontium ferrite photocatalyst for photocatalytic degradation of the rhodamine B dye.