Structural and optical properties of Ce doped BiFeO ₃ nanoparticles via sol–gel method

Abstract

The effect of Ce doping on the structural and optical properties of BiFeO 3 nanoparticles via sol-gel method is reported. All samples were a pure phase with perovskite structure. The EDX results show the doped samples contain Bi, Fe, O and Ce elements. The vibrational properties of samples were studied using Raman spectroscopy. Photoluminescence shows an intense peak at 398 nm, the peak strength enhanced greatly and had redshift with the increase of Ce doping concentration. UV-vis results show the samples have a broad absorption band in the range of 500-600 nm. The bandgaps decrease with the concentration increase of Ce doping. It indicates the as-prepared BiFeO 3 can be used as visible light catalyst.

Rapid Synthesis of Pure Phase Bismuth Ferrite through Modified Sol‐gel Auto‐ignition Method: Impact of Different Chelating Agents

“…However the E1 (76 cm −1) result doesn't include in the test result, as the Raman spectra were collected in the range 100–700 cm −1 . The as‐prepared samples represents 12 modes (4 A1+8E), which are in a good agreement with the previous studies [60,61] . Three A1 modes (A1‐1, A1‐2, and A1‐3) were observed at frequency band range 139–141, 173–174 and 219–222 cm −1 , respectively; corresponds to the Bi−O bond at the tetrahedral site.…”

“…The as-prepared samples represents 12 modes (4 A1 + 8E), which are in a good agreement with the previous studies. [60,61] Three A1 modes (A1-1, A1-2, and A1-3) were observed at frequency band range 139-141, 173-174 and 219-222 cm À 1 , respectively; corresponds to the BiÀ O bond at the tetrahedral site. Moreover, the E modes observed at frequency more than 400 cm À 1 corresponds to the FeÀ O bond at the octahedral site.…”

Hydrothermal synthesis of Ce/Zr co-substituted BiFeO3: R3c-to-P4mm phase transition and enhanced room temperature ferromagnetism

“…A similar increase in optical band gap is also reported for Y and Co co-doping of BFO due to a decrease in the density of state in the valence band [42]. However, there are contradictory reports on the effect of Ce substitution on the bandgap energy of BFO [43][44][45]. Here, the increase of the gap energy cannot be originated the shift of the optical bandgap, with increasing Ce content (Ce acts as a donor) [7,[41][42][43][44][45].…”

“…However, there are contradictory reports on the effect of Ce substitution on the bandgap energy of BFO [43][44][45]. Here, the increase of the gap energy cannot be originated the shift of the optical bandgap, with increasing Ce content (Ce acts as a donor) [7,[41][42][43][44][45]. These will lead to a shift in the fundamental absorption edge towards higher photon energy.…”

The facile synthesis of and light-driven water splitting on a hetero-metallic bismuth oxide catalyst

“…Among the aforementioned bismuth-based perovskite oxides, iron, cerium, and barium as a dopant have been found to boost the efficiency of the material as a catalyst, which can be attributed to the following reasons: (i) the presence of barium and iron is very effective not only due to the creation of active metal centers favorable for oxidation of water but also its earth-abundant, cost-effective nature, 30 (ii) it is also expected that Ce doping could also induce structural distortions to improve the electrical and magnetic properties of the oxides. 39,40 Furthermore, the ionic radius of the Ce 4+ ion is closer to that of the Bi 3+ ion, and the chemical stability and valence of the Ce 4+ ion are higher than those of the Bi 3+ ion; thus, the Ce substitution for Bi appears particularly appealing. 41 However, the energy-conversion efficiencies of these bismuth-based perovskite systems remain poor when compared to other narrow-band-gap semiconductors, which is considered to be a consequence of the absence of efficient charge separation as well as the extremely short lifetime of non-thermalized electrons in bulk perovskite oxides.…”