Heterojunction of BiPO 4 /BiOBr photocatalysts for Rhodamine B dye degradation under visible LED light irradiation

Oxygen Vacancies-Rich S-Cheme BiOBr/CdS Heterojunction with Synergetic Effect for Highly Efficient Light Emitting Diode-Driven Pollutants Degradation

Recently, the use of semiconductor-based photocatalytic technology as an effective way to mitigate the environmental crisis attracted considerable interest. Here, the S-scheme BiOBr/CdS heterojunction with abundant oxygen vacancies (Vo-BiOBr/CdS) was prepared by the solvothermal method using ethylene glycol as a solvent. The photocatalytic activity of the heterojunction was investigated by degrading rhodamine B (RhB) and methylene blue (MB) under 5 W light-emitting diode (LED) light. Notably, the degradation rate of RhB and MB reached 97% and 93% in 60 min, respectively, which were better than that of BiOBr, CdS, and BiOBr/CdS. It was due to the construction of the heterojunction and the introduction of Vo, which facilitated the spatial separation of carriers and enhanced the visible-light harvest. The radical trapping experiment suggested that superoxide radicals (·O₂^-) acted as the main active species. Based on valence balance spectra, Mott-Schottky(M-S) spectra, and DFT theoretical calculations, the photocatalytic mechanism of the S-scheme heterojunction was proposed. This research provides a novel strategy for designing efficient photocatalysts by constructing S-scheme heterojunctions and introducing oxygen vacancies for solving environmental pollution.

Highly Efficient Bi4Ti3O12/g-C3N4/BiOBr Dual Z-Scheme Heterojunction Photocatalysts with Enhanced Visible Light-Responsive Activity for the Degradation of Antibiotics

A novel Bi₄Ti₃O₁₂/g-C₃N₄/BiOBr(BTO/CN/BOB) composite was synthesized by a solvothermal-mechanical mixed thermal method. The composition, structure, and micromorphology of the samples were analyzed. The BTO/CN/BOB composite photocatalyst shows better photocatalytic performance for tetracycline hydrochloride (TC) degradation compared to Bi₄Ti₃O₁₂ and binary composite photocatalysts. The highest degradation rate of TC can reach 89.84% using the BTO/CN/BOB photocatalyst under the optimal conditions, and BTO/CN/BOB still exhibits good photocatalytic properties after recycling. Moreover, it also shows good photodegradation activity for different kinds of antibiotics, implying its wide application prospect. The photocatalytic performance and reuse stability of BTO/CN/BOB were significantly improved, which may be because of the enhanced spectral absorption range and efficient electron transfer capability by the synergistic effect and interaction among Bi₄Ti₃O₁₂, BiOBr, and g-C₃N₄. Finally, the possible degradation pathway and electron transfer mechanism of the dual Z-scheme heterojunction are proposed.

Superhydrophobic Self-Supporting BiOBr Aerogel for Wastewater Purification

This research was focused on the raw material level construction of bismuth oxybromide (BiOBr) catalysis-loaded 3D cross-linked network polyurethane (PU) foam via the in situ polymerization method. After modification of superhydrophobic polydivinylbenzene nanoparticles, the PU foam possessed excellent superhydrophobic stability. The larger selective absorption oil phase capacity depended on its macroporous structure, and the existence of catalyst BiOBr (the band gap energy was about 2.57 eV) among the PU foam played a crucial role in degrading water-soluble contaminants under visible light irradiation. In this article, the photocatalytic experiment results verify that it has remarkable recycle degradation ability (the degradation efficiency can reach ∼97%) and the capture experiments indicate that the uppermost active species is h⁺.