Controllable Microwave Hydrothermal Synthesis of Bismuth Ferrites and Photocatalytic Characterization

Abstract

The process, by which three kinds of bismuth ferrites (BiFeO 3 , Bi 25 FeO 40 , and Bi 25 FeO 40 -BiFeO 3 ) were synthesized for 1 h through a microwave hydrothermal method by changing the KOH concentration and the temperature, is summarized in this article. The as-prepared bismuth ferrite powders were characterized by the X-ray diffraction, the field emission scanning electron microscopy, and the transmission electron microscope, and the band gaps, specific surface areas, photocatalytic and magnetic properties were explored as well. The results showed that the degradation degree of methyl orange using BiFeO 3 , Bi 25 FeO 40 , and Bi 25 FeO 40 -BiFeO 3 as catalyst were 35%, 52%, and 90% at 2 h, respectively, and the magnetizations of the three powders were 0.07, 3.17, and 0.55 emu/g, respectively. This indicated that the porous cubic Bi 25 FeO 40 -BiFeO 3 powder has the best photocatalytic property of the three, making it useful as a new type of photocatalytic material which can be easily recycled by magnetic separation.

Dielectric properties of BiFeO3 ceramics obtained from mechanochemically synthesized nanopowders

“…In the case of our BFO ceramics obtained from mechanochemically synthesized nanopowders, the MTDR can be attributed to the combined effect of the grain boundary and the presence of secondary Bi 25 FeO 40 phase acting as an additional internal barrier layer making the heterogeneity more complex. The secondary phase can be considered as a semiconducting one due to its energy gap of 1.78 eV [41]. The activation energy of 1.0 eV is slightly higher compared to that of BFO obtained from pure precipitation-synthesized powder, probably due to the increase in the heterogeneity.…”

Synthesis of Pt/BiFeO3 heterostructured photocatalysts for highly efficient visible-light photocatalytic performances

“…The narrow band gap of BFO allows its visible light response to become possible. Some studies have confirmed the photocatalytic activity of BFO materials under visible light irradiation [15][16][17]. For instance, Gao et al [18] reported that BFO nanoparticles exhibited photocatalytic degradation activity for methyl orange upon visible light irradiation.…”

Structural, magnetic and photocatalytic properties of La and alkaline co-doped BiFeO3 nanoparticles

“…Photocatalytic degradation is considered as an efficient way for the removal of dye contaminants from water [9]. Various research articles are published on the photocatalytic activity of pure BFO nanoparticles synthesized using different methods like hydrothermal [10,11], sol-gel [12,13], ultrasonic radiation [9], autocombustion [14] for degradation of rhodamine B (RhB), solvothermal [15] for degradation of methylene blue (MB), microwave-hydrothermal [16], co-precipitation [17] for degradation of methyl orange (MO) and hydrothermal [18] for degradation of congo red. There are only a few reports on the influence of dopant modified BFO on the photocatalytic degradation of organic dyes.…”