Magnetic and photocatalytic properties of BiFeO3 nanoparticles formed during the heat treatment of hydroxides coprecipitated in a microreactor with intense swirling flows

In this work, hydroxide deposition in a microreactor with intensively swirling flows was used to obtain BiFeO 3 , followed by heat treatment of co-precipitated bismuth and iron hydroxides.The study of the formation of nanocrystalline bismuth orthoferrite was carried out using a set of methods: EDXMA, TEM, XRD, 57 Fe M össbauer spectroscopy, DRS, etc.The photocatalytic activity and magnetic characteristics of the material were determined.It is shown that during heat treatment of hydroxide precipitation for 1 minute at a temperature of 530 • C, BiFeO 3 nanocrystals with an average crystallite size of 14±7 nm are formed.It was found that the resulting BiFeO 3 nanopowder is represented by agglomerates of individual nanoparticles.The saturation magnetization and residual magnetization values of these bismuth orthoferrite nanoparticles are 2.31 and 0.48 emu/g, respectively.According to the DRS results, band gap energy for the samples calculated at 530, 515, and 500 • C were 1.82, 1.86, and 1.91 eV, respectively, which ensures strong absorption of visible light by the samples.The sample showed higher photocatalytic activity in the X-ray amorphous state compared with nanocrystalline BiFeO 3 in the process of Fenton-like discoloration of methyl violet under the action of visible light with reaction rate constants of the pseudo-first order 0.0256 and 0.0072 min -1 , respectively.