Spark Plasma Sintering-Assisted Synthesis of Bi2Fe4O9/Bi25FeO40 Heterostructures with Enhanced Photocatalytic Activity for Removal of Antibiotics

Abstract

Bismuth ferrite-based heterojunction composites have been considered as promising visible-light responsive photocatalysts because of their narrow band gap structure; however, the synthetic methods reported in the literature were usually time-consuming. In this study, we report a facile and quick preparation of bismuth ferrite-based composites by the hydrothermal method, combined with spark plasma sintering (SPS), a technique that is usually used for the high-speed consolidation of powders. The result demonstrated that the SPS-assisted synthesized samples possess significant enhanced photoelectric and photocatalytic performance. Specifically, the SPS650 (sintered at the 650 °C for 5 min by SPS) exhibits a 1.5 times enhancement in the photocurrent density and a 3.8 times enhancement in the tetracycline hydrochloride photodegradation activity than the unmodified bismuth ferrite samples. The possible influence factors of SPS on photoelectric and photocatalytic performance of bismuth ferrite-based composites were discussed carefully. This study provides a feasible method for the facile and quick synthesis of a highly active bismuth ferrite-based visible-light-driven photocatalyst for practical applications.

Aggregation-based growth of faceted Bi2Fe4O9 micro-cuboids with a remarkable visible light photo-Fenton catalytic activity

“…7(c) in the UV-vis diffuse reflectance spectrum should be considered as the d–d electron transition of Fe 3+ resulting from the energy splitting of the Fe 3d orbital. 23,33 Thus, the intrinsic bandgap of the as-synthesized Bi 2 Fe 4 O 9 micro-cuboids should be determined to be 2.01 eV, which is consistent with the reported result. 16 From the above results, it can be inferred that the as-synthesized Bi 2 Fe 4 O 9 micro-cuboids could be attractive for potential visible or solar light photocatalysis.…”

“…This implies that the as-synthesized Bi 2 Fe 4 O 9 micro-cuboid sample is possibly a specific multiband semiconductor with double bandgaps. 16,32,33 Moreover, the second absorption peak at 824 nm observed in Fig. 7(c) in the UV-vis diffuse reflectance spectrum should be considered as the d–d electron transition of Fe 3+ resulting from the energy splitting of the Fe 3d orbital.…”

Metal–Organic Framework-Templated Synthesis of In2S3/CoSx Nanocages for Photocatalytic Removal of Antibiotics

“…Generally, the design and construction of heterojunctions can effectively enhance photocatalytic performance. − Heterostructures constructed by two-phase photocatalysts with matched energy band structures tend to form potential gradients, which promote the separation and transformation of photoinduced charges. Specifically, metal sulfide-based heterojunction composites not only exhibit a wider visible-light absorption range but also greatly suppress recombination rates of photogenerated charges.…”

Crystal Structure, Magnetic and Photocatalytic Properties of Solid SolutionsBi2‐xLaxFe4O9 (x=0.05, 0.1)

“…Bi 2 Fe 4 O 9 can be synthesized by different approaches: hydrothermal method, [19] PVA sol‐gel route, [20] reverse chemical co‐precipitation, [21] spark plasma sintering, [22] etc. Bi 2 Fe 4 O 9 substituted by different metals to improve its properties are published as well.…”