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1.
J Environ Sci (China) ; 148: 437-450, 2025 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-39095178

RESUMO

For environmental applications, it is crucial to rationally design and synthesize photocatalysts with positive exciton splitting and interfacial charge transfer. Here, a novel Ag-bridged dual Z-scheme Ag/g-C3N4/CoNi-LDH plasmonic heterojunction was successfully synthesized using a simple method, with the goal of overcoming the common drawbacks of traditional photocatalysts such as weak photoresponsivity, rapid combination of photo-generated carriers, and unstable structure. These materials were characterized by XRD, FT-IR, SEM, TEM UV-Vis/DRS, and XPS to verify the structure and stability of the heterostructure. The pristine LDH, g-C3N4, and Ag/g-C3N4/CoNi-LDH composite were investigated as photocatalysts for water remediation, an environmentally motivated process. Specifically, the photocatalytic degradation of tetracycline was studied as a model reaction. The performance of the supports and composite catalyst were determined by evaluating both the degradation and adsorption phenomenon. The influence of several experimental parameters such as catalyst loading, pH, and tetracycline concentration were evaluated. The current study provides important data for water treatment and similar environmental protection applications.


Assuntos
Nanocompostos , Fotólise , Prata , Poluentes Químicos da Água , Purificação da Água , Nanocompostos/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Prata/química , Catálise , Nitrilas/química , Compostos de Nitrogênio/química , Adsorção , Grafite
2.
Chemosphere ; 364: 143227, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39218258

RESUMO

In this study, visible light-activated photocatalyst oxygen-doped C3N4@Bi12O17Cl2 (OCN@BOC) and Fe(VI) coupling system was proposed for the efficient degradation of bisphenol A (BPA). The comprehensive characterization of the OCN@BOC photocatalyst revealed its excellent photogenerated carrier separation rate in heterogeneous structures. The OCN@BOC/Fe(VI)/Vis system exhibited a remarkable BPA removal efficiency of over 84% within 5 min. Comparatively, only 37% and 59% of BPA were degraded by single OCN@BOC and Fe(VI) in 5 min, respectively. Reactive species scavenging experiments, phenyl sulfoxide transformation experiments, and electron paramagnetic resonance experiments confirmed the involvement of superoxide radicals (⋅O2-), singlet oxygen (1O2), as well as iron(V)/iron(IV) (Fe(V)/Fe(IV)) species in the degradation process of BPA. Furthermore, density functional theoretical calculations and identification of intermediates provided insights into the potential degradation mechanism of BPA during these reactions. Additionally, simulation evaluations using an ecological structure activity relationship model demonstrated that the toxicity of BPA to the ecological environment was mitigated during its degradation process. This study presented a novel strategy for removing BPA utilizing visible light photocatalysts, highlighting promising applications for practical water environment remediation with the OCN@BOC/Fe(VI)/Vis system.


Assuntos
Compostos Benzidrílicos , Luz , Oxigênio , Fenóis , Compostos Benzidrílicos/química , Fenóis/química , Oxigênio/química , Catálise , Ferro/química , Poluentes Químicos da Água/química , Fotólise , Bismuto/química
3.
Chemosphere ; 364: 143240, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39222696

RESUMO

Iron(II)-based metal organic framework (Fe(II)-MOF) nanosheets have emerged as promising candidates for photo-Fenton catalysis. However, efficiently synthesizing Fe(II)-MOF nanosheets remains a significant challenge. Here, a bottom-up synthesis strategy is proposed to prepare two-dimensional Fe-MOF nanosheets (TFMN) with micrometer lateral dimensions and nanometer thickness, featuring Fe(II) as the metal nodes. The application of TFMN in the photo-Fenton degradation of carbamazepine (CBZ) demonstrates remarkable CBZ degradation performance and excellent efficiency across a wide range of pH values. The electron density and density of states are further calculated by density functional theory. Mechanism analysis identifies h+, •OH and •O2- as the predominant active species contributing to the catalytic oxidation process in the Vis/TFMN/H2O2 system.


Assuntos
Carbamazepina , Peróxido de Hidrogênio , Ferro , Estruturas Metalorgânicas , Nanoestruturas , Oxirredução , Carbamazepina/química , Estruturas Metalorgânicas/química , Peróxido de Hidrogênio/química , Ferro/química , Catálise , Nanoestruturas/química , Poluentes Químicos da Água/química
4.
Heliyon ; 10(16): e35829, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39253175

RESUMO

Ciprofloxacin antibiotic (CP) is one of the antibiotics with broad-spectrum antimicrobial activity that has the highest rate of antibiotic resistance. This antibiotic undergoes incomplete metabolism within the human body and is excreted into the water, resulting in its hazardous biological and ecotoxicological effects. In this study, a novel photocatalyst, comprised of graphitic carbon nitride (g-CN) and Tetrakis(acetonitrile)copper(I)hexafluorophosphate ([(CH3CN)4Cu]PF6), denoted as CuPF6/g-CN, was employed for the degradation of ciprofloxacin under visible-light irradiation. The Cu complex, functioning as a co-catalyst, assumes a crucial role in facilitating the efficient separation of photogenerated charges and exhibiting high absorption in the visible-light region. More surprisingly, CuPF6/g-CN does surpass by up to 6 times the behavior reached with bare g-CN. The experimental findings indicated that the optimal degradation of ciprofloxacin (CP) occurred after 50 min when using a concentration of 20 mg L-1 CP and a concentration of 0.05 g/L CuPF6/g-CN, under a pH of 8. This research offers valuable insights into the advancement of cost-effective co-catalysts that enhance the photocatalytic capabilities of established photocatalysts. It contributes to improving the overall performance and efficiency of these photocatalytic systems.

5.
ACS Appl Mater Interfaces ; 16(37): 49411-49427, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39238429

RESUMO

The precise synthesis of ultrasmall, monodisperse CsPbBr3 nanocrystals is crucial due to their enhanced photophysical properties resulting from strong quantum confinement effects. Traditional methods struggle with size control, complicating synthesis. Although CsPbBr3 nanocrystals find applications in LEDs and photovoltaics, their use in photocatalysis for organic reactions remains limited. Our study introduces ultrasmall TBIA-CsPbBr3 nanocrystals (∼5.6 nm), synthesized via a three-precursor hot injection method using tribromoisocyanuric acid (TBIA) as a bromine precursor for the first time. These nanocrystals exhibit a near-unity photoluminescence quantum yield (PLQY) of 0.99 and an elevated oxidation potential of +1.80 V. We demonstrate their efficacy as recyclable heterogeneous photocatalysts in a one-pot, 100% E-selective, anti-Markovnikov sulfinylsulfonation of terminal alkynes under visible light, achieving a high product conversion rate (PCR) of 62,500 µmol g-1 h-1 and recyclability for up to five cycles. Density functional theory (DFT) calculations support the exclusive formation of the E-isomer. TBIA-CsPbBr3 outperforms other CsPbBr3 perovskites in photocatalysis, with superior efficiency attributed to their extended excited-state lifetime and higher surface area, which accelerates the organic transformation process.

6.
Sci Rep ; 14(1): 21341, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39266647

RESUMO

The Gd-doped ZnO/SnO2 nanocomposites with various atomic percentages (0, 0.5, 0.8, and 1.2 at%) of gadolinium (coded as GdZS0, GdZS1, GdZS2, and GdZS3) was synthesis via the sol-gel method and explored for photodegradation against dye solutions exposing solar light irradiation. The synthesized nanocomposites were characterized employing the XRD, FTIR, FE-SEM, Raman spectroscopy, BET analysis and UV-Vis spectrophotometer. The FE-SEM results indicated that the formation of nanoparticles to nanoflowers covered with Gd ions was observed with an increased doping concentration of Gd. The optical bandgap was evaluated and found in the range of 3.21-3.27 eV for GdZS nanocomposites. The GdZS nano-photocatalysts were investigated against the degradation of different organic dyes and GdZS3 shows the highest degradation efficiencies of 99.3%, 98.3% and 99.4% towards MO, MB and RhB dyes, respectively at neutral pH in aqueous media. Before and after photodegradation. Biological oxygen demand and chemical oxygen demand tests to make estimations of mineralization. The investigations are very promising for the degradation process in rare earth doped metal oxide nanocomposites. A plausible photodegradation mechanism of synthesized nanocomposites under investigation has also been proposed.

7.
J Environ Manage ; 370: 122543, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39305881

RESUMO

Soil pollution by microplastics (MPs) is an escalating environmental crisis with far-reaching consequences. However, current research on the degradation and/or remediation of MPs has mainly focused on water-simulated environments, with little attention given to soil MPs. Therefore, the review explores such terrestrial territory, exploring the potential of biodegradation and novel photocatalytic technologies for MPs degradation/remediation in soil. This review comprehensively investigates the potential of biological and photocatalytic approaches for soil MPs degradation and remediation. A temporal analysis of research from 2004 to 2024 highlights the increasing focus on this critical issue. The review explores the biocatalytic roles of diverse enzymes, including cutinase, PETase, MHETase, hydrolase, lipase, laccase, lignin peroxidase, and Mn-peroxidase, in MPs degradation. Strategies for enzyme engineering, such as protein engineering and immobilization, are explored to enhance catalytic efficiency. The potential for developing enzyme consortia for optimized MP degradation is also discussed. Photocatalytic remediation using TiO2, ZnO, clay, hydrogel, and other photocatalysts is examined, emphasizing their mechanisms and effectiveness. Computational modeling is proposed to deepen understanding of soil MPs-catalyst interactions, primarily aiming to develop novel catalysts tailored for soil environments for environmental safety and sustainable restoration. A comparative analysis of biological and photocatalytic approaches evaluates their environmental implications and the potential for synergistic combinations, with emphasis on soil quality protection, restoration and impact on soil ecosystems. Hence, this review accentuates the urgent need for innovative solutions to address MPs pollution in soil and provides a foundational understanding of the current knowledge gaps, as well as paves the way for future research and development.

8.
Chemosphere ; 365: 143347, 2024 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-39284552

RESUMO

Improving the charge separation, charge transfer, and effective utilization is crucial in a photocatalysis system. Herein, we prepared a novel direct Z-scheme NH2-MIL-125(Ti)@FeOCl (Ti-MOF@FeOCl) composite photocatalyst through a simple method. The prepared composite catalyst was utilized in the photo-Fenton degradation of Rhodamine B (RhB) and ciprofloxacin (CIP). The Ti-MOF@FeOCl (10FeTi-MOF) catalyst exhibited the highest catalytic performance and degraded 99.1 and 66% of RhB and CIP, respectively. However, the pure NH2-MIL-125(Ti) (Ti-MOF) and FeOCl catalysts achieved only 50 and 92% of RhB and 50 and 37% of CIP, respectively. The higher catalytic activities of the Ti-MOF@FeOCl composite catalyst could be due to the electronic structure improvements, photoinduced charge separations, and charge transfer abilities in the catalyst system. The composite catalysts have also enhanced adsorption and visible light-responsive properties, allowing for efficient degradation. Furthermore, the electron paramagnetic resonance (EPR) signals, the reactive species trapping experiments, and Mott-Schottky (M - S) measurements revealed that the photogenerated superoxide radical (•O2-), hydroxyl radical (•OH), and holes (h+) played a vital role in the degradation process. The results also demonstrated that the Ti-MOF@FeOCl heterojunction composite catalysts could be a promising photo-Fenton catalyst system for the environmental remediation. Environmental implications The discharging of toxic contaminants such as organic dyes, antibiotics, and other emerging pollutants to the environment deteriorates the ecosystem. Specifically, the residues of organic pollutants recognized as a threat to ecosystem and a cause for carcinogenic effects. Among them, ciprofloxacin is one of antibiotics which has biological resistance, and metabolize partially in the human or animal bodies. It is also difficult to degrade ciprofloxacin completely with traditional treatment methods. Similarly, organic dyes are also toxic and a cause for carcinogenic effects. Therefore, effective degradation of organic pollutants such as RhB and ciprofloxacin with appropriate method is crucial.

9.
Angew Chem Int Ed Engl ; : e202417474, 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39323208

RESUMO

Supramolecular assembly allows multiple chemical/bio-components integrated as one system for cascade biochemical reactions. Herein the graphitic carbon nitrides (g-C3N4) as photocatalyst trapped in a dipeptide hydrogel covering adenosine triphosphate (ATP) synthase accelerates the photophosphorylation through ATP synthesis. Self-assembled N-fluorenylmethoxycarbonyl diphenylalanine (Fmoc-FF) as nanofibrils to allow g-C3N4 nanosheets are embedded as a complex Fmoc-FF/g-C3N4 hydrogel. Fmoc-FF gel exhibits good electronic coupling with g-C3N4, which enables a photo-induced proton generation. The transmembrane proton gradient can be established by ATP synthase-lipid reconstituted on the surface of the Fmoc-FF/g-C3N4 hydrogel to enhance the ATP synthesis. It indicates that the Fmoc-FF/g-C3N4/ATP synthase-lipid film can possess a longer-term ATP production capability and allow repeated immersion for sustained ATP production. Such a hydrogel-supported ATP synthesis platform is achieved by a procedure at a larger scale.

10.
Turk J Chem ; 48(4): 550-567, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39296786

RESUMO

In this study, we developed a heterojunction photocatalyst, namely nitrogen-doped carbon quantum dots/titanium dioxide (N-CQDs/TiO2), for the effective and sustainable treatment of ciprofloxacin (CIP) antibiotic in aqueous solution. First, N-CQDs were prepared from a chitosan biopolymer with a green, facile, and effective hydrothermal carbonization technique and then anchored on the TiO2 surface via a hydrothermal process. The morphological, structural, and optical properties of the as-prepared materials were characterized by using advanced analytical techniques. The impacts of the mass percentage of N-CQDs, catalyst and CIP concentration, and pH on photocatalytic CIP degradation were investigated in depth. Comparative analyses were performed to evaluate different processes including adsorption, photolysis, and photocatalysis for the removal of CIP with TiO2 and N-CQDs/TiO2. The results revealed that N-CQDs/TiO2 exhibited the highest CIP removal efficiency of up to 83.91% within 120 min using UVA irradiation under optimized conditions (10 mg/L CIP, 0.4 g/L catalyst, and pH 5). Moreover, the carbon source used in the fabrication of N-CQDs was also considered, and lower removal efficiency was obtained when glucose was used as a carbon source instead of chitosan. This excellent improvement in CIP degradation was attributed to the ideal separation and migration of photogenerated carriers, strong redox capability, and high generation of reactive oxygen species provided by the successful construction of the N-CQDs/TiO2 S-scheme heterojunction. Scavenger experiments indicated that h+ and •OH reactive oxygen species were the predominant factors for CIP elimination in water. Overall, this study presents a green synthesis approach for N-CQDs/TiO2 heterojunction photocatalysts using natural materials, demonstrating potential as a cost-effective and efficient method for pharmaceutical degradation in water treatment applications.

11.
Chemistry ; : e202402690, 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39261993

RESUMO

We propose a new class of H2 evolution photocatalyst containing TMD not as a co-catalyst, but as a photosensitizer: MoSe2/C60-dendron nanohybrids, assisted by 1-benzyl-1,4-dihydronicotinamide (BNAH) as a sacrificial donor and Pt nanoparticles as co-catalysts. The 2D/0D mixed-dimensional heterojunction formed by MoSe2 and C60 is highly effective in generating mobile carriers under visible and NIR light irradiation.  This process involves electron extraction from the exciton in MoSe2 to C60, followed by electron transfer to Pt nanoparticles via MV2+, leading to H2 production from water.  Even NIR light, such as 800 nm light corresponding to the A-exciton absorption of MoSe2, can facilitate water splitting.  The EQY of the H2 evolution reaction was estimated to be 0.0027%.

12.
ChemSusChem ; : e202401489, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39223088

RESUMO

Lignin valorization through heterogeneous photocatalysis is a promising pathway for obtaining value-added products, including chemical building blocks, biofuels, etc. However, several challenges still demand attention and resolution in this field. One of the key parameters in the heterogeneous photocatalytic process is the synthesis of efficient photocatalysts that can accomplish efficient and selective reactions. Selective conversion of lignin can be achieved by using heterojunction photocatalysts which can efficiently separate charge carriers' and promote selective reactions by band structure modulation. This work details a straightforward approach for synthesizing heterojunction photocatalysts based on Bi4Ti3O12 and BiOI involving the hydrothermal and co-precipitation methods. Additionally, the synthesized composites were employed in the selective oxidation of veratryl alcohol, a lignin-derived model compound, to produce high-value-added veratraldehyde. The experimental results showed that the BiOI/Bi4Ti3O12 heterojunction (12.5 mol % BiOI) showed superior activity with a veratraldehyde yield of 5.4 and 27.2 times higher than those of Bi4Ti3O12 and BiOI, respectively. The mechanistic studies revealed that the improved activity and selectivity were due to the enhanced charge carriers' separation and the suppression of reactive oxygen species formation through modulation of band structure. This study allows a green approach to lignin-derived biomass valorization to obtain high-value chemicals.

13.
Angew Chem Int Ed Engl ; : e202413012, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39231037

RESUMO

Allylic C-H amination has emerged as a powerful tool to construct allylamines, common motifs in molecular therapeutics. Such reaction implies an oxidative path for C-H activation but furnishes reductive amines, inferring mild oxidants' inactivity for C-H oxidation but strong oxidants' detriment to products. Herein we report a heterogeneous catalytic approach that manipulates halogen-vacancies of perovskite photocatalyst and exploits halogenated-solvents (i.e. CH2Cl2, CH2Br2) as mild oxidants for selective C-H allyl amination with 19,376 turnover. CsPbBr3 nanocrystals induce cooperative hydrogen-atom-transfer (HAT, C-H oxidation, and halogen-vacancy CsPbBr3-x formation) and halogen-atom-transfer (XAT, CsPbBr3-x-induced solvent reduction) under a radical chain mechanism. Terminal/internal olefins are amenable to forge aromatic/aliphatic, cyclic/acyclic, secondary/tertiary allylamines (70 examples), including drugs or their derivatives.

14.
Adv Mater ; : e2406848, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39233544

RESUMO

Photocatalytic water splitting has become a very popular research subject in recent years. Consequently, it is important to report appropriately standardized experimental data, so that each researcher can properly understand the results generated by others. However, experimental methods and measures of photocatalytic performance are not yet sufficiently systematic. In the present manuscript, experimental procedures and standardization of photocatalytic performance are described in relation to the basic theory of photocatalytic water splitting.

15.
J Colloid Interface Sci ; 678(Pt B): 984-991, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39270398

RESUMO

In this work, combining the density functional theory (DFT) calculations and the ab initio molecular dynamics (AIMD) simulations, the water adsorption behavior, including the molecular and the dissociative adsorption on the negatively polarized (0 0 1) surface of ferroelectric PbTiO3 was comprehensively studied. Our theoretical results show that the dissociative adsorption of water is more energetically favorable than the molecular adsorption on the pristine PbTiO3 (0 0 1) surface. It has been also found that introducing surface oxygen vacancies (OV) can enhance the thermodynamic stability of dissociative adsorption of water molecule. The AIMD simulations demonstrate that water molecule can spontaneously dissociate into hydrogen atoms (H) and hydroxyl groups (OH) on the pristine PbTiO3 (0 0 1) surface at room temperature. Moreover, the surface OV can effectively facilitate the dissociative adsorption of water molecules, leading to a high surface coverage of OH group, thus giving rise to a high reactivity for water splitting on defective PbTiO3 (0 0 1) surface with OV. Our results not only comprehensively understand the reason for the photocatalytic water oxidation activity of single domain PbTiO3, but also shed light on the development of high performance ferroelectric photocatalysts for water splitting.

16.
J Colloid Interface Sci ; 678(Pt B): 1135-1147, 2024 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-39278039

RESUMO

The serious combination of abundant electrons/holes in bulk primarily hinders the efficiency in the photocatalytic reaction. It is crucial to control the spatial charge dynamics through delicately designing the crystal configuration of photocatalyst. In this work, a modified tungsten trioxide nanosheet colloid (M-WO3) was synthesized by an ion exchange method. Compared to pristine WO3 (P-WO3), the crystal lattice vibration frequency of M-WO3 increases from 2.8 meV to 4.3 meV, which effectively prohibits electron-phonon coupling and powerfully accelerates the separation and transfer of photoinduced charge carriers. Irradiated by visible-light, M-WO3 shows much higher photocatalytic bacterial inactivation performance than P-WO3. In addition, this regulation method increases the surface charges of the WO3 colloid to improve its stability, which endows this colloid photocatalyst with broad prospects in practical photocatalytic antibacterial applications. This work offers guidance to construct efficiently separated photoinduced electron/hole pairs of the colloid photocatalyst by designing its crystal structure.

17.
Angew Chem Int Ed Engl ; : e202412090, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39292412

RESUMO

Photocatalytic reduction of CO2 into C2,3 hydrocarbons completes a C-neutral cycle. The reaction pathways of photocatalytic generation of C2,3 paraffin and C2H4 from CO2 are mostly unclear. Herein, a Co0-ZrO2 photocatalyst converted CO2 into C1-3 paraffin, while selectively converting CO into C2H4 and C3H6 (6.0 ± 0.6 µmol h-1 gcat-1, 70 mol%) only under UV-visible light. The photocatalytic cycle was conducted under 13CO and H2, with subsequent evacuation and flushing with CO. This iterative process led to an increase in the population of C2H4 and C3H6 increased up to 61-87 mol%, attributed to the accumulation of CH2 species at the interface between Co0 nanoparticles and the ZrO2 surface. CO2 adsorbed onto the O vacancies of the ZrO2 surface, with resulting COH species undergoing hydrogenation on the Co0 surface to yield C1-3 paraffin using either H2 or H2O (g, l) as the reductant. In contrast, CO adsorbed on the Co0 surface, converted to HCOH species, and then split into CH and OH species at the Co and O vacancy sites on ZrO2, respectively. This comprehensive study elucidates intricate photocatalytic pathways governing the transformation of CO2 into paraffin and CO to olefins.

18.
Chemistry ; : e202402705, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39226120

RESUMO

Decarboxylative alkylation of carboxylic acids with easily oxidizable functional groups such as phenol and indole functionalities was achieved using a catalytic amount of basic iron(III) acetate, Fe(OAc)2(OH), in the presence of benzimidazole under 427 nm LED irradiation. Kinetic analyses of this catalytic reaction revealed that the reaction rate is first-order in alkenes and is linearly correlated with the light intensity; the faster reaction rate for the benzimidazole-ligated species was consistent with the increased absorbance in the visible light region. Wide functional group tolerance for the easily oxidizable groups is ascribed to the weak oxidation ability of the in situ-generated oxo-bridged iron clusters compared with other iron(III) species.

19.
J Colloid Interface Sci ; 678(Pt A): 959-969, 2024 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-39226836

RESUMO

Bismuth oxybromide (BiOBr) nanomaterials are well-known efficient powder-shaped photocatalyst for degrading antibiotic wastewater, but their practical applications have been limited by unsatisfactory photo-absorption, weak photocatalytic activity and poor recyclability. To address these issues, we demonstrate that the growing of S-doped BiOBr nanosheets on carbon fiber cloth (CFC) can lead to efficient photocatalysis with recyclable features. With carbon fiber cloth as the substrate, S-doped BiOBr (BiOBr-Sx) nanosheets (diameter: ∼500 nm, thicknesses: ∼5-90 nm) was prepared by solvothermal method with thiourea as dopant. With the increase of thiourea (0-0.2 g) in the precursor solution, BiOBr-Sx nanosheets exhibit a significant shift in the photo-absorption edge from 420 to 461 nm and decreased thicknesses from 90 to 5 nm, accompanying by the increased proportion of (010) exposed surface. Amony them, CFC/BiOBr-S0.5 can degrade various contaminants (such as 98.7 % levofloxacin (LVFX), 95.6 % ciprofloxacin (CIP) and 95.9 % tetracycline (TC)) with most degradation efficiency within 120 min of visible light irradiation, which are 1.6, 1.9 and 1.4 times than that of CFC/BiOBr (61.4 % LVFX, 49.5 % CIP and 67.1 % TC), respectively. Significantly, when CFC/BiOBr-S0.05 photocatalytic fabric is combined with a multi-stage flow device to treat the flowing wastewater (10 mg/L LVFX, rate: 1 L/h), 91.0 % LVFX can be degraded after tenth grade. Therefore, this study not only demonstrates the controllable preparation of S-doped BiOBr nanosheets with different thickness on CFC but also highlights the practical applications of fabric-based photocatalysts for purifying the flowing sewage efficiently.

20.
J Colloid Interface Sci ; 678(Pt A): 987-1000, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39226839

RESUMO

Photocatalytic wastewater purification is essential for environmental remediation, but rapid carrier recombination and limited oxidative capacity hinder progress. This study proposes an innovative strategy by integrating homogeneous and heterogeneous electron acceptors into a g-C3N4-based photocatalytic system, significantly enhancing the multipath utilization of photogenerated electrons. A novel Fe3O4@P-C3N4 was developed to activate an advanced peroxymonosulfate-assisted photocatalysis (PAP) system, achieving complete degradation and significant mineralization of tetracycline (TC) in real water environments, outperforming others reported in the last five years. Phytic acid, as a key precursor, modifies the hollow tubular morphology and introduces phosphorus (P) heteroatoms as electronic trapping centers, enhancing the visible light response and carrier separation, thereby promoting the Fe2+/Fe3+ cycle and the formation of reactive species. Density functional theory (DFT) calculations pinpointed TC's vulnerable sites and synergically identified reactive species, revealing almost non-toxic degradation processes. Moreover, the recyclable magnetic Fe3O4@P-C3N4/PAP system demonstrates practical application potential and leaching stability in cyclic and continuous testing. This study offers unique insights into the strategic design of photocatalysts and catalytic environments, potentially advancing practical wastewater remediation.

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