Oxygen-functionalized Ti3C2 MXene/exfoliated montmorillonite supported S-scheme BiOBr/Bi2MoO6 heterostructures for efficient photocatalytic quinolone antibiotics degradation

Photocatalytic activation of persulfate has been receiving much attention in the field of wastewater treatment. In this work, the Bi 3 NbO 7 /BiOBr 0.75 I 0.25 nanosheet S-scheme heterojunctions were synthesized by the solvothermal method to activate persulfate. The degradation rates of rhodamine B (RhB) and TC by 0.05Bi 3 NbO 7 / BiOBr 0.75 I 0.25 were 95.4 and 74.7% in 2 h, respectively, indicating that 0.05Bi 3 NbO 7 /BiOBr 0.75 I 0.25 nanosheet heterojunctions have good photocatalytic activity. The synergistic effect between persulfate and the 0.05Bi 3 NbO 7 /BiOBr 0.75 I 0.25 photocatalyst was investigated under different persulfate contents, pH values, and light conditions. The RhB degradation rate of 0.05Bi 3 NbO 7 /BiOBr 0.75 I 0.25 activation persulfate is more than twice that of 0.05Bi 3 NbO 7 /BiOBr 0.75 I 0.25 , and the range of pH adaptation is wide. Radical quenching experiments showed that h + , • O 2 − , and •OH were the important active groups. Persulfate and catalysts produce a synergistic effect, which is S 2 O 8 2− reacting with e − to form •SO 4 − in the photocatalytic process. Meanwhile, the formation of •SO 4 − accelerates the process of photocatalytic reaction. This work provides ideas for the design of efficient and pollution-free photocatalysts for the activation of persulfate.

Section: Resultssupporting

confidence: 84%

Persulfate Activation of Photocatalysts Based on S-Scheme Bi₃NbO₇/BiOBr_0.75I_0.25 Nanosheet Heterojunctions for Degradation of Organic Pollutants

Wang

et al. 2023

“…To explain the reason for photocurrent enhancement, the light absorption capacity of the samples was first evaluated by detecting the UV–vis–NIR absorption spectra, and the results are displayed in Figure b. Clearly, Ti 3 C 2 T x presented excellent light absorption ability in the entire wavelength range, while Bi 2 S 3 only exhibited strong absorption at UV and visible light regions. , Compared with Bi 2 S 3 , the absorption spectrum of Bi 2 S 3 /Ti 3 C 2 T x appears to be a new absorption peak in the range of 650–900 nm, indicating that the absorption of NIR light has been enhanced, which is more conducive to capturing photon energy to generate a photocurrent. , Furthermore, the energy band gap ( E g ) of the photoelectric material could also affect the generation of the photocurrent . Therefore, the E g of Bi 2 S 3 and Bi 2 S 3 /Ti 3 C 2 T x were calculated by the Tauc relation (eq ).…”

Section: Resultsmentioning

confidence: 99%

“…32,33 It should be noted that both the binding energies of Bi 4f and S 2p of Bi 2 S 3 /Ti 3 C 2 T x shifted to higher binding energy as compared with that of Bi 2 S 3 . The increase in binding energy means a decrease in the local electron density of Bi and S 34,35 Compared with Bi 2 S 3 , the absorption spectrum of Bi 2 S 3 /Ti 3 C 2 T x appears to be a new absorption peak in the range of 650−900 nm, indicating that the absorption of NIR light has been enhanced, which is more conducive to capturing photon energy to generate a photocurrent. 36,37 Furthermore, the energy band gap (E g ) of the photoelectric material could also affect the generation of the photocurrent.…”

Section: Synthesis and Characterization Of Bimentioning

confidence: 99%

Photoelectric Bi₂S₃ Nanoparticle/Ti₃C₂T_x Nanosheet Heterojunction for Promotion of Nerve Cell Growth

Chen

et al. 2023

Bismuth sulfide (Bi2S3) enabled us to transform light signals into electrical signals via the photoelectric effect, which exhibited tremendous prospects on constructing wireless electrical stimulation for accelerating nerve regeneration. However, too rapid recombination of photogenerated electron–hole pairs weakened its photocurrent. Herein, the Bi2S3/Ti3C2T x heterojunction was synthesized by in situ growth of Bi2S3 nanoparticles on Ti3C2T x nanosheets and then mixed with poly-l-lactic acid (PLLA) powder to fabricate the Bi2S3/Ti3C2T x -PLLA conduit. At the heterojunction interfaces, Ti3C2T x with a more positive Fermi energy level could form interfacial potential difference with Bi2S3 to promote electron–hole pair separation. Meanwhile, Ti3C2T x with excellent conductivity could provide channels for photogenerated electron transmission, thus facilitating the generation of the photocurrent. Photoluminescence and electrochemical impedance spectroscopy analysis indicated that electron–hole pair separation and electron transfer were enhanced. As a consequence, under near-infrared light radiation, the output photocurrent of Bi2S3/Ti3C2T x -PLLA was increased from 0.48 to 1.43 μA compared to that of Bi2S3-PLLA. The enhanced photocurrent effectively promoted the differentiation of rat pheochromocytoma (PC12) into functional neurons by upregulating extracellular Ca2+ influx. Therefore, the above results demonstrated that this work provided a new perspective for wireless electrical stimulated nerve regeneration.

“…The transient photocurrents of the catalysts were depicted in Figure 5c, with the weaker photocurrents of Sn-TiO 2 and BiOBr indicating that the presence of Coulomb potential energy resulted in the rapid complexation of pure Sn-TiO 2 and BiOBr carriers. 51 In contrast, the BiOBr nanosheets in TSB-0.5 became thinner and provided better catalyst utilization due to the introduction of Sn-TiO 2 , which increased the photoinduced cavity redox potential and reduced carrier complexation in synergy with the heterojunction.…”

Section: Morphology and Structurementioning

confidence: 99%

Thickness Modification of BiOBr Nanosheets by Sn-TiO₂ for Enhanced Photocatalytic Degradation of Antibiotics

Ying

Xie

et al. 2023

Modification of morphological engineering to enhance photocatalytic activity has been considered an effective strategy. However, effective modification of the catalyst nanosheet thickness remains a difficult challenge to control. Here, we have synthesized Sn-TiO 2 /BiOBr composite photocatalysts by a onepot method. With the addition of Sn-TiO 2 , the flakes of BiOBr gradually became thinner, resulting in more surface reaction site, and Sn-TiO 2 clearly increased the adsorption capacity of the composite catalyst. The degradation efficiency of the prepared Sn-TiO 2 /BiOBr (the atomic ratio of titanium/bismuth 1:1) was 98% and 80% for TC-HCl and CIP, respectively, showing good photocatalytic performance. Furthermore, the radical trapping experiments revealed that h + and •O 2 − play an important role in the Sn-TiO 2 /BiOBr system. Photoelectrochemical tests and photoluminescence confirm that the thin sheets can significantly improve carrier migration efficiency in Sn-TiO 2 /BiOBr heterojunctions. Finally, the degradation mechanism of the Sn-TiO 2 /BiOBr system was elucidated using UV-DRs and Mott−Schottky curves. Experimental analysis shows that modulating the thickness of BiOBr nanosheets with Sn-TiO 2 can promote the exposure of surface reaction sites, can enhance their light adsorption ability and carrier mobility, and is a promising method for improving photocatalytic efficiency.