Facile synthesis of pure BiFeO3 and Bi2Fe4O9 nanostructures with enhanced photocatalytic activity

Abstract

In the present work, pure BiFeO 3 and pure Bi 2 Fe 4 O 9 single phases were successfully synthesized by tailoring hydrothermal synthesis route. The structural and morphology analyses have been achieved by X-ray diffraction and by electron microscopy. Scanning and transmission electron microscopy images revealed a strong change in the morphology from agglomerated nanoparticles with sizes less than 10 nm for BiFeO 3 to plate-like particles with larger sizes (edges of 100 to 200 nm while a thickness of * 30 nm) for Bi 2 Fe 4 O 9 . Such a small size obtained for BFO nanoparticles has never been observed before for similar synthesis method without any added reagents, to the best of our knowledge. The photocatalytic activity of the as-prepared samples for degradation of methylene blue dye under sunlight irradiation shows a good efficiency. It reaches 61% and 83% after 3 h for BiFeO 3 and Bi 2 Fe 4 O 9 nanostructures, respectively. Despite a bigger size and higher bandgap, the better efficiency of Bi 2 Fe 4 O 9 compared to BiFeO 3 is explained by a much stronger absorption especially for light with energy higher than 2.65 eV.

Impact of Crystallite Size and Phase Boundaries on Magnetic and Thermoelectric Properties of Cu-Added BiFeO3

“…16 After that, as-synthesized BFO contains the secondary phase of Bi 2 Fe 4 O 9 . 17 The selected dopant Cu was placed in the CuBi 2 O 4 phase due to the early formation of this phase with rising temperatures. Usually, the secondary phases of BFO exist in a cocentric spherical model with a rising temperature.…”

Effect of Zn Substitution on the Structural, Optical Properties and Photocatalytic Activity of BiFeO3 Nanopowders

“…The mixture was stirred for 1 h to form a homogeneous solution and then transferred into a Teflon‐lined stainless steel autoclave of 50 mL capacity for heating. The heating treatment was performed at for 6 h. The product was washed with nitric acid and distilled water, collected by centrifugation and dried at 80 °C for 3 h [ 49 ] . The structural phase of as‐prepared powder was characterized by X‐Ray diffraction (XRD) on a Bruker D2 phaser diffractometer using Cu Kα radiation ( λ = 1.5406 Å) source in a wide‐angle range (20°≤2 θ ≤ 80).…”

Photodegradation of Xanthate Using a Bi2Fe4O9/ZnIn2S4 Heterojunction: Experimental and DFT Studies

“…18 BFO has great photocatalytic activity in organic photodegradation because of its strong response to visible light. 19,20 Furthermore, ZIS has higher conduction band (CB) and valence band (VB) potentials than BFO. 21,22 Therefore, forming a type II or Z-scheme heterojunction between ZIS and BFO is deemed feasible, which can improve charge transfer and inhibit the recombination of photogenerated carriers.…”

“…Bi 2 Fe 4 O 9 (BFO), a bismuth ferrite, has been widely used in catalysis, electromagnetism, and gas sensor fields due to its narrow band gap (1.9–2.3 eV), chemical stability, and environmental friendliness . BFO has great photocatalytic activity in organic photodegradation because of its strong response to visible light. , Furthermore, ZIS has higher conduction band (CB) and valence band (VB) potentials than BFO. , Therefore, forming a type II or Z-scheme heterojunction between ZIS and BFO is deemed feasible, which can improve charge transfer and inhibit the recombination of photogenerated carriers. , To the best of our knowledge, however, BFO/ZIS nanocomposites have not been reported yet.…”