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1.
J Environ Sci (China) ; 150: 657-675, 2025 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-39306437

RESUMO

The uncontrolled release of antibiotics into the environment would be extremely harmful to human health and ecosystems. Therefore, it is in urgent need to monitor the environment and promote the detection and degradation of antibiotics to the relatively harmless by-products to a feasible extent. Graphitic carbon nitride (g-C3N4) is a non-metallic n-type semiconductor that can be used for the antibiotic detection and degradation due to its easy synthesis process, excellent chemical stability and unique optical properties. Unfortunately, the utilization of visible light, electron-hole recombination and electron conductivity have hindered its potential applications in the fields of photocatalytic degradation and electrochemical detection. Although previous publications have highlighted the diverse modification methods for the g-C3N4-based materials, the underlying structure-performance relationships of g-C3N4, especially for the detection and degradation of antibiotics, remains to be further explored. In view of this, the current review centered on the recent progress in the modification techniques of g-C3N4, the detection and degradation of antibiotics using the g-C3N4-based materials, as well as the potential antibiotic degradation mechanisms of the g-C3N4-based materials. Additionally, the underlying applications of the g-C3N4-based materials for antibiotic detection and degradation were also prospected. This review would provide a valuable research foundation and the up-to-date information for the g-C3N4-based materials to combat antibiotic pollution in the environment.


Assuntos
Antibacterianos , Grafite , Compostos de Nitrogênio , Grafite/química , Antibacterianos/análise , Antibacterianos/química , Compostos de Nitrogênio/química , Compostos de Nitrogênio/análise , Monitoramento Ambiental/métodos , Nitrilas/química , Nitrilas/análise
2.
J Environ Sci (China) ; 149: 149-163, 2025 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-39181630

RESUMO

Developing heterojunction photocatalyst with well-matched interfaces and multiple charge transfer paths is vital to boost carrier separation efficiency for photocatalytic antibiotics removal, but still remains a great challenge. In present work, a new strategy of chloride anion intercalation in Bi2O3 via one-pot hydrothermal process is proposed. The as-prepared Ta-BiOCl/Bi24O31Cl10 (TBB) heterojunctions are featured with Ta-Bi24O31Cl10 and Ta-BiOCl lined shoulder-by-shouleder via semi-coherent interfaces. In this TBB heterojunctions, the well-matched semi-coherent interfaces and shoulder-by-shoulder structures provide fast electron transfer and multiple transfer paths, respectively, leading to enhanced visible light response and improved photogenerated charge separation. Meanwhile, a type-II heterojunction for photocharge separation has been obtained, in which photogenerated electrons are drove from the CB (conduction band) of Ta-Bi24O31Cl10 to the both of bilateral empty CB of Ta-BiOCl and gathered on the CB of Ta-BiOCl, while the photogenerated holes are left on the VB (valence band) of Ta-Bi24O31Cl10, effectively hindering the recombination of photogenerated electron-hole pairs. Furthermore, the separated electrons can effectively activate dissolved oxygen for the generation of reactive oxygen species (·O2-). Such TBB heterojunctions exhibit remarkably superior photocatalytic degradation activity for tetracycline hydrochloride (TCH) solution to Bi2O3, Ta-BiOCl and Ta-Bi24O31Cl10. This work not only proposes a Ta-BiOCl/Bi24O31Cl10 shoulder-by-shoulder micro-ribbon architectures with semi-coherent interfaces and successive type-II heterojunction for highly efficient photocatalytic activity, but offers a new insight into the design of highly efficient heterojunction through phase-structure synergistic transformation strategy.


Assuntos
Antibacterianos , Bismuto , Poluentes Químicos da Água , Bismuto/química , Antibacterianos/química , Poluentes Químicos da Água/química , Catálise , Processos Fotoquímicos
3.
J Environ Sci (China) ; 149: 512-523, 2025 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-39181663

RESUMO

Oxygen activation leading to the generation of reactive oxygen species (ROS) is essential for photocatalytic environmental remediation. The limited efficiency of O2 adsorption and reductive activation significantly limits the production of ROS when employing C3N4 for the degradation of emerging pollutants. Doping with metal single atoms may lead to unsatisfactory efficiency, due to the recombination of photogenerated electron-hole pairs. Here, Mn and S single atoms were introduced into C3N4, resulting in the excellent photocatalytic performances. Mn/S-C3N4 achieved 100% removal of bisphenol A, with a rate constant 11 times that of pristine C3N4. According to the experimental results and theoretical simulations, S-atoms restrict holes, facilitating the photo-generated carriers' separation. Single-atom Mn acts as the O2 adsorption site, enhancing the adsorption and activation of O2, resulting the generation of ROS. This study presents a novel approach for developing highly effective photocatalysts that follows a new mechanism to eliminate organic pollutants from water.


Assuntos
Oxigênio , Poluentes Químicos da Água , Poluentes Químicos da Água/química , Oxigênio/química , Catálise , Manganês/química , Compostos Benzidrílicos/química , Nitrilas/química , Adsorção , Espécies Reativas de Oxigênio , Recuperação e Remediação Ambiental/métodos , Fenóis/química
4.
J Colloid Interface Sci ; 677(Pt A): 994-1004, 2025 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-39128293

RESUMO

Photocatalysts are one of the effective methods to degrade antibiotic contamination, but the efficiency is low and the toxicity is not well recognized. Deep lattice doping to induce defect generation is an effective way to improve the performance of photocatalysts. Here, defect-rich bromine-doped BiOCl-XBr photocatalysts were constructed with the help of small molecules inserted into the interlayer. The photocatalytic degradation performance of BiOCl-XBr was significantly enhanced, and its degradation rate was up to about 12 times that of BiOCl monomer. The main reasons for the stronger photocatalytic performance of BiOCl-XBr include Br doping to enhance visible light absorption, surface defects, and Bi valence changes to improve charge transport. The degradation of tetracycline (TC) produced more toxic intermediates, and the biotoxicity experiments also confirmed that the toxicity showed a trend of increasing and then decreasing, indicating that the more toxic intermediates were also mineralized during the degradation process. However, the mortality and hatching rate of zebrafish in the exposed group after degradation recovered but changed their activity pattern under light and dark conditions. This further warns us to focus on the toxicity changes after antibiotic degradation. Finally, based on the free radical analysis, the mechanism of photocatalytic degradation and detoxification of TC by BiOCl-XBr was proposed.


Assuntos
Antibacterianos , Bismuto , Bromo , Tetraciclina , Peixe-Zebra , Tetraciclina/química , Tetraciclina/farmacologia , Bismuto/química , Animais , Catálise , Antibacterianos/química , Antibacterianos/farmacologia , Bromo/química , Processos Fotoquímicos , Luz , Fotólise , Propriedades de Superfície
5.
J Colloid Interface Sci ; 677(Pt A): 1052-1068, 2025 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-39134080

RESUMO

Levofloxacin (LVX) is difficult to be naturally degraded by microorganisms in water, and its residues in water will pose significant risks to human health and ecological environment. In this study, Bi12O17Cl2 was used as the main body, Bi12O17Cl2/GO/Co3O4 composite photocatalyst was prepared by pyrolysis of zeolitic imidazolate framework-67 (ZIF-67) combined with in-situ precipitation method and used to degrade LVX. A sequence of characterizations shows that addition of Co3O4 and graphene oxide (GO) increases the visible light response range, improves the separation efficiency of photogenerated electrons and holes (e--h+) of photocatalyst, and thus improves the degradation efficiency of LVX. Under the optimal reaction conditions, the LVX degradation rate of Bi12O17Cl2/1.5GO/7.5Co3O4 can reach 91.2 % at 120 min, and its reaction rate constant is the largest (0.0151 min-1), which is 2.17, 13.14 and 1.53 times that of Bi12O17Cl2, Co3O4 and Bi12O17Cl2/7.5Co3O4, respectively, showing better photocatalytic performance. Simultaneously, the recycling stability of Bi12O17Cl2/1.5GO/7.5Co3O4 was also verified. The capture experiments and electron EPR test results showed that superoxide radicals (•O2-) and photogenerated holes (h+) were the primary active substances in the reaction process. Finally, combined with HPLC-MS results, the photocatalytic degradation pathway of LVX was derived. This work will provide a theoretical basis for the design of Metal Organic Frameworks (MOFs)-derivative modified Bi12O17Cl2-based photocatalysts.

6.
Heliyon ; 10(20): e39042, 2024 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-39497981

RESUMO

The widespread use of imidacloprid (IMI) in pest control presents significant environmental challenges due to its persistence and low removal efficiency. This study introduces magnetic Covalent Organic Frameworks (COFs) functionalized with Fe3O4 nanoparticles (Fe3O4@HMN-COF, Fe3O4@MAN-COF, and Fe3O4@SIN-COF) as efficient adsorbents for IMI removal from water. These COFs, engineered with nitrogen-rich structures and extensive π-electron systems, achieve superior adsorption through π-π interactions, hydrophobic interactions, and hydrogen bonding. Characterization via FT-IR, XRD, and nitrogen sorption isotherms confirmed their high hydrophilicity, stability, and large surface areas. The magnetic properties of the COFs facilitated easy separation from water, enhancing practicality. Kinetic studies for all COFs indicated a pseudo-second-order model, suggesting chemisorption, with adsorption capacities of 600 mg/g for Fe3O4@HMN-COF, 480 mg/g for Fe3O4@MAN-COF, and 375 mg/g for Fe3O4@SIN-COF. Thermodynamic analyses revealed spontaneous and endothermic adsorption processes. Reusability tests showed minimal capacity loss over multiple cycles, underscoring their practical applicability. Practical tests in honey and fruit samples confirmed high efficacy, demonstrating the COFs' versatility. The study also optimized the photocatalytic degradation of imidacloprid using these COFs, with Fe3O4@HMN-COF achieving 98.5 % efficiency under optimal conditions (10 mg L-1 IMI, 0.01 g catalyst dose, pH 11, 30 °C, UV light). These findings highlight the potential of magnetic COFs for sustainable environmental remediation of pesticide-contaminated water.

7.
ChemSusChem ; : e202401408, 2024 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-39498989

RESUMO

The urgent need to mitigate water pollution and achieve Sustainable Development Goal 14 (SDG 14)-Life below water, necessitates developing efficient and eco-friendly wastewater treatment technologies. This research addresses this challenge by photocatalytic degradation of terephthalic acid, a precursor for PET bottles using environment-friendly and biocompatible photocatalysts. The 1D/2D nanocomposite comprising zinc oxide (ZnO) nanorods and functionalized graphitic carbon nitride (Zn-TG) nanosheets were synthesized and thoroughly characterized. The nanocomposite effectively mitigated the individual drawbacks of Zn-TG agglomeration and the wide band gap of ZnO as confirmed through zeta potential and Tauc's plot studies, respectively. The synthesized nanocomposite achieved ~100 % degradation within 60 minutes, exhibiting superior kinetics (~2.5 times) compared to pristine samples. The enhanced degradation efficiency was elucidated by efficient charge carrier transfer (~5 times faster) and separation (~2 times improved) as confirmed through electrochemical impedance spectroscopy and time-resolved photoluminescence studies. The proposed Z-scheme pathway provides mechanistic insights. This proposed mechanism is supported by extensive electron paramagnetic resonance (EPR) and scavenger studies. The liquid chromatography-mass spectrometry (LC-MS) analysis confirms the formation of less toxic byproducts for ensuring that the wastewater treatment process is efficient and environmentally friendly. This research helps in developing a highly effective and sustainable wastewater treatment technology.

8.
Glob Chall ; 8(9): 2400093, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39440228

RESUMO

Magnetically separable Fe3O4, Fe3O4@SiO2, Fe3O4@SiO2@ZnO, and Fe3O4@SiO2@ZnO-Ag composites are synthesized using hydrothermal and wet chemistry methods. The samples obtained are characterized in terms of morphology, composition, optical, and magnetic properties using TEM, SEM-EDS, XRD, FTIR, VSM, XPS, and UV-vis, and the photodegradation of Acid Blue 161 dye under UV irradiation is investigated. As a result of SEM and TEM analyses, the diameters of Fe3O4, Fe3O4@SiO2, Fe3O4@SiO2@ZnO, and Fe3O4@SiO2@ZnO-Ag composites are determined as 210, 220, 230 and 235 nm, respectively. The magnetic properties of the samples are determined by VSM analysis. In VSM analyses, magnetization saturation values of Fe3O4, Fe3O4@SiO2, Fe3O4@SiO2@ZnO, and Fe3O4@SiO2@ZnO-Ag composites are determined as 81, 64, 41 and 20 emus × g-1, respectively. In XRD analysis, the face-centered cubic structure of Fe3O4 particles and the hexagonal wurtzite structure of ZnO are determined and it is determined that they are compatible with standard diffraction cards. According to UV-Vis analysis, E g values for Fe3O4, Fe3O4@SiO2, Fe3O4@SiO2@ZnO, and Fe3O4@SiO2@ZnO-Ag composites are found as 1.3, 1.68, 2.21, and 2.15 eV, respectively. Among the photocatalysts prepared, Fe3O4@SiO2@ZnO-Ag composite Acid Blue 161 shows superior removal and recyclability against photodegradation of the dyestuff.

9.
Spectrochim Acta A Mol Biomol Spectrosc ; 326: 125284, 2024 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-39447300

RESUMO

This study explores a novel method for detecting neonicotinoid insecticides, imidacloprid (IMD) and dinotefuran (DNT), in water using terbium (Tb3+) ions photo probe. The optimal excitation and emission wavelengths for Tb3+ luminescence were identified at 310 nm and 545 nm, respectively. The influence of pH and solvent on Tb-complex fluorescence was investigated. Results indicate a significant enhancement of luminescence intensity at pH 6 for IMD in DMF and pH 7.0 for DNT in DMSO. The fluorescence intensity exhibited a linear relationship with IMD and DNT concentrations ranging from 0.1 to 20 µg/mL (R2 > 0.99). Limits of quantitation (LOQ) were determined as 0.1 µg/mL for IMD and 0.05 µg/mL for DNT. This newly developed photo probe demonstrates the potential for monitoring photolysis and photocatalytic degradation of these neonicotinoids using TiO2 as a catalyst under controlled photoreactor conditions. The method offers a promising alternative for rapidly and sensitively detecting these prevalent insecticides in water samples.

10.
J Colloid Interface Sci ; 679(Pt A): 10-20, 2024 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-39353352

RESUMO

The photocatalytic degradation of polychlorinated biphenyls (PCBs) is advancing, yet the efficiency of degradation within the visible spectral range continues to encounter significant challenges. In this study, two biochar-based organic semiconductor photocatalysts, Active Carbon@PTQ10 (5,8-Dibromo-6,7-difluoro-2-(2-hexyldecoxy)quinoxaline; trimethyl-(5-trimethylstannylthiophen-2-yl)stannane): ITIC-Th (Propanedinitrile,2,2'-[[6,6,12,12-tetrakis(5-hexyl-2-thienyl)-6,12-dihydrodithieno[2,3-d: 2',3'-d'] -s-indaceno[1,2-b:5,6-b'] dithiophene-2,8-diyl] bis[methylidyne(3-oxo-1H-indene-2,1(3H)-diylidene)]] bis-) (AC@PI) and Active Carbon@PTQ10: PC71BM (6,6)-phenyl C71 butyric acid methyl ester), were synthesized using a wide bandgap material, PTQ10, as the electron donor, along with a non-fullerene material, ITIC-Th, and a fullerene material, PC71BM, as the acceptors, respectively. Under optimized conditions, AC@PI degraded 93.4 % of 2,2 ',4,4 '-tetrachlorobiphenyl (PCB 47) within 60 min. By incorporating a non-fullerene acceptor (ITIC-Th), AC@PI exhibits a larger surface photopressure, a lower hole-electron transfer ratio, a broader absorption spectrum (400 - 1000 nm), and enhanced structural stability. AC@PI can generate photogenerated electrons and holes, as well as superoxide anions (O2-) and hydroxyl radicals (OH), through type II heterojunctions, which contributes to its exceptional properties. This study synthesized novel organic semiconductor catalysts that offer a green, efficient, and non-toxic method for the degradation of aromatic pollutants, such as polychlorinated biphenyls.

11.
Molecules ; 29(19)2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39407493

RESUMO

The large-scale utilization of antibiotics has opened a separate chapter of pollution with the generation of reactive drug-resistant bacteria. To deal with this, in this work, different mass ratios of CoFe2O4/WO3 nanocomposites were prepared following an in situ growth method using the precursors of WO3 and CoFe2O4. The structure, morphology, and optical properties of the nanocomposite photocatalysts were scrutinized by X-ray diffraction (XRD), UV-visible diffuse reflectance spectra (UV-Vis DRS), photoluminescence spectrum (PL), etc. The experimental data signified that the loading of CoFe2O4 obviously changed the optical properties of WO3. The photocatalytic performance of CoFe2O4/WO3 composites was investigated by considering tetracycline as a potential pollutant. The outcome of the analyzed data exposed that the CoFe2O4/WO3 composite with a mass ratio of 5% had the best degradation performance for tetracycline eradication under the solar light, and a degradation efficiency of 77% was achieved in 20 min. The monitored degradation efficiency of the optimized photocatalyst was 45% higher compared with the degradation efficiency of 32% for pure WO3. Capturing experiments and tests revealed that hydroxyl radical (·OH) and hole (h+) were the primary eradicators of the target pollutant. This study demonstrates that a proper mass of CoFe2O4 can significantly push WO3 for enhanced eradication of waterborne pollutants.


Assuntos
Antibacterianos , Cobalto , Nanocompostos , Óxidos , Tetraciclina , Tungstênio , Tungstênio/química , Nanocompostos/química , Catálise , Antibacterianos/química , Antibacterianos/farmacologia , Óxidos/química , Tetraciclina/química , Cobalto/química , Compostos Férricos/química , Fotólise , Poluentes Químicos da Água/química , Difração de Raios X , Processos Fotoquímicos
12.
Int J Mol Sci ; 25(19)2024 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-39408585

RESUMO

Titanium dioxide thin films on the inner wall of quartz tubes were prepared in situ by the sol-gel method. Meanwhile, copper and cerium were loaded onto the surface of the titanium dioxide thin films to enhance photocatalytic activity and broaden the range of light absorption. X-ray diffractometer, X-ray photoelectron spectroscopy, scanning electron microscopy, energy dispersive X-ray spectrum, N2 gas adsorption, UV diffuse reflectance spectroscopy, electron paramagnetic resonance, photoluminescene spectroscopy, and so on were used to characterize the structure, morphology, chemical composition, and optical properties of the prepared photocatalyst. Methylene blue (MB) was used as a simulated organic pollutant to study the photocatalytic performance of the photocatalyst, which was a translucent, structurally stable, and reusable high-efficiency photocatalytic catalyst. Under UV lamp irradiation, the MB photodegradation efficiency was 94.5%, which reached 91.2% after multiple cycles.


Assuntos
Fotólise , Quartzo , Titânio , Titânio/química , Catálise , Quartzo/química , Azul de Metileno/química , Raios Ultravioleta , Cobre/química , Difração de Raios X , Espectroscopia Fotoeletrônica
13.
Molecules ; 29(19)2024 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-39407666

RESUMO

Construction of S-scheme heterojunctions can effectively limit the recombination of photogenerated e- and h+, thus improving photocatalytic activity. Therefore, S-scheme ZnO/BiOCl (molar ratio = 1:2) n-n heterojunctions were synthesized via a hydrothermal-hydrolysis combined method in this study. The physical and chemical properties of the ZnO/BiOCl heterojunctions were characterized by XRD, XPS, SEM, TEM, DRS, N2 adsorption-desorption and ESR. Additionally, the photoelectric performances of ZnO/BiOCl heterojunctions were investigated with TPR, M-S plot and EIS. The results show that photocatalytic degradation of NOR by ZnO/BiOCl reached to 94.4% under simulated sunlight, which was 3.7 and 1.6 times greater than that of ZnO and BiOCl, respectively. The enhanced photodegradation ability was attributed to the enhancement of the internal electric field between ZnO and BiOCl, facilitating the active separation of photogenerated electrons and holes. The radical capture experiments and ESR results illustrate that the contribution of reactive species was in descending order of ·OH > h+ > ·O2- and a possible mechanism for the photodegradation of NOR over S-scheme ZnO/BiOCl heterojunctions was proposed.

14.
Sci Rep ; 14(1): 23393, 2024 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-39379438

RESUMO

Plant-mediated synthesized materials are receiving more attention than conventional ones due to their wide availability, ease of access, simple preparation methods, environmental benign, and possess superior physicochemical properties. In this work, plant extract-mediated CuO, Bi2O3, and CuO/Bi2O3 nanocomposite samples were successfully synthesized using bamboo leaves extract as a capping agent. These materials were utilized for the photodegradation of Rhodamine B (RhB) dye, which served as a model organic dye pollutant. The physicochemical characterization techniques such as XRD, SEM-EDS, FTIR, and DRS-UV-vis spectrophotometry provide insight into the crystal structure, morphology, surface functional groups, and optical properties. These analyses confirm the effective formation of CuO, Bi2O3, and CuO/Bi2O3 materials. Surprisingly, upon calcination at 450 °C for 4 h, the color of the nanocomposite changed from pale green to gray greenish, providing evidence for the formation of the CuO in CuO/Bi2O3 nanocomposite. The photocatalytic optimization parameters such as pH (4), catalyst load (35 mg), irradiation time (180 min) and concentration of RhB (10 mg L-1) dye were investigated. By coupling CuO with Bi2O3 nanoparticles resulted in an improved photocatalytic property for the degradation of RhB dye under optimal conditions. As a result, CuO/Bi2O3 nanocomposite exhibited a significantly boosted photocatalytic degradation efficiency (95.6%) compared to pure CuO (40.2%) and Bi2O3 (80.5%) photocatalysts, with good reusability. For comparison purpose, the photocatalytic degradation of RhB dye using selected photocatalyst was evaluated under dark and sunlight systems. This eco-friendly approach holds great potential for synthesis new nanocomposite with modified properties, thereby enabling the practical application of high-efficiency photocatalysts. The plausible mechanism of the electrons and holes transfer was proposed.

15.
Small ; : e2404303, 2024 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-39422106

RESUMO

The realization of fast carrier transport can effectively enhance photocatalytic performance. A core-shell structure of ZnO and In2O3 is successfully constructed by using MIL-68 (In) and ZIF-8 as a substrate, forming a heterojunction. This MOF-derived core-shell heterojunction inherits the advantages of ZIF-8, with pores facilitating carriers transfer to the surface for reactions and a large specific surface area providing more active sites. This Z-scheme heterojunction of ZnO and In2O3 can effectively separate and improve the utilization of photogenerated carriers. The well-designed interface of the core-shell structure achieves the rapid transfer of photogenerated carriers. The photocatalytic degradation capability of ZnO@ In2O3 is enhanced by the synergistic effect of Z-scheme heterojunction and core-shell structure. This work provides insight into the investigation of constructing core-shell heterojunctions.

16.
Front Chem ; 12: 1411980, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39398193

RESUMO

Industrial dye effluent causes significant risks to the environment. The present study was focused on photocatalytic degradation of the dye Direct Red 28 using a ternary composite of graphitic carbon nitride, TiO2, and polyorthoanisidine (g-C3N4/TiO2/POA), prepared by in-situ oxidative polymerization o-anisidine. The synthesized composite g-C3N4/TiO2/POA properties were characterized using different analytical techniques. X-ray diffraction (XRD) results revealed the prominent pattern of TiO2 and g-C3N4 in the composite peak at 2θ° while Fourier transform infrared (FTIR) results provided the confirmation peaks for g-C3N4/TiO2/POA and POA at 1,110 cm-1 and 1,084 cm-1 for C-O-C ether. Scanning electron microscopy (SEM) demonstrated an increase in the average size of the composite up to 428 nm. The energy-dispersive X-ray spectroscopy (EDX) spectrum provided the weight percentages of the C, O, and Ti in the composite were 8.5%, 45.69%, and 45.81%, respectively. The photocatalytic degradation of Direct Red 28 dye under UV irradiation using a composite showed that 86% Direct Red 28 dye was degraded by a 30 mg/L dose of g-C3N4/TiO2/POA in 240 min at pH 2. After four consecutive cycles, the utilized composite showed 79% degradation of Direct Red 28, demonstrating the stability and effectiveness of the g-C3N4/TiO2/POA photocatalyst. The high reusability and efficiency of the g-C3N4/TiO2/POA composite are due to increased light absorption range and reduced e-/h+ recombination rate in the presence of g-C3N4 and POA.

17.
Environ Res ; 263(Pt 2): 120060, 2024 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-39368594

RESUMO

Developing advanced strategies, including exposing active site centers, regulating coordination environments, controlling crystallographic facets, optimizing electronic structures and constructing defects for enhancing photocatalytic performance is of great significance to improving the ecosystem. In this study, a novel self-assembled bimetallic Fe/Mn-MOF with SnS2 Z-scheme heterojunction photocatalyst was designed using a facile multistep solvothermal method. Benefiting from the interfacial heterojunction synergistic effect, the photocatalysts exhibited an outstanding catalytic performance. Nearly 91.4% efficiency of tetracyclines was degraded within 80 min through the assistance of a persulfate-based advanced oxidation process. DFT calculations utilizing the Fukui index identified the sites vulnerable to attack by the active species. As demonstrated by the trapping experiments and electron spin resonance (ESR), the involved oxygen-active species (•O2- and 1O2) facilitated the rapid degradation of tetracycline. The degradation pathways were further guided in the elucidation of the rationale mechanism and the toxicity of derived intermediates was revealed. This work opens a new strategy for the rational design of bimetallic photocatalysts, emphasizing interface-modulated heterojunctions for efficient solar energy conversion.

18.
Int J Biol Macromol ; 282(Pt 3): 137035, 2024 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-39476884

RESUMO

Herein, nitrogen-doped nickel hexacyanoferrate (N@NiHCF) nanoparticles were prepared via co-precipitation and incorporated in guar gum (GG)-Xanthan gum (Xa) based-polymeric-matrix (GGXa@N@NiHCF) for efficient removal of rose bengal (RB) dye and nonyl phenol (NP) pollutants under sunlight. PXRD, FESEM, XPS, and FTIR analysis verified successful integration of N@NiHCF nanoparticles into GGXa matrix. Scherrer and Williamson-Hall equations estimated average-crystallite sizes of GGXa@N@NiHCF nanoparticles to be 16.34 nm. TGA analysis and zeta potential values (-17.7 mV for N@NiHCF and -22.9 mV for GGXa@N@NiHCF nanocomposite) confirmed structural stability. N@NiHCF has band gap of 2.3 eV, demonstrating enhanced photocatalytic efficiency due to improved light absorption and charge separation. Photocatalytic experiments demonstrated high degradation rates of RB (91 %) in 150 min and NP (95 %) in 300 min under optimized conditions highlighting composite's effectiveness. Kinetics of photodegradation process were studied using Hinshelwood formula, yielding rate constant of 0.93 min-1 (t1/2 = 0.74 h) for RB and 0.60 min-1 (t1/2 = 1.14 h) for NP with GGXa@N@NiHCF. LC-MS analysis identified degradation pathways, indicating transformation of pollutants into safer byproducts. Recyclability study showed sustained performance over multiple cycles, emphasizing nanocomposite's durability. This study provides insights into applying GGXa@N@NiHCF, highlighting its promise as a sustainable approach for mitigating water pollution.

19.
Chemosphere ; 366: 143518, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39419337

RESUMO

Microplastics (MPs), plastic particles smaller than 5 mm, are pervasive pollutants challenging wastewater treatment due to their size and hydrophobicity. They infiltrate freshwater, marine, and soil environments, posing ecological threats. In marine settings, MPs ingested by organisms cause cytokine release, cellular and DNA damage, and inflammation. As MPs enter the food chain and disrupt biological processes, their degradation is crucial. While biodegradation, pyrolysis, and chemical methods have been extensively studied, the use of metal-organic frameworks (MOFs) for MP pollution mitigation is underexplored. In this study, we explored the photocatalytic degradation mechanisms of MPs by MOFs in aquatic environments. We analyzed the hydrolysis, oxidation, and adsorption processes, while focusing on the environmentally friendly and cost-effective photocatalytic approach. Additionally, we analyzed the literature on MP decomposition for various types of MOFs, providing a detailed understanding of the degradation mechanisms specific to each MOF. Furthermore, we evaluated the degradation efficiencies of different MOFs and discussed the challenges and limitations in their application. Our study highlights the need for an integrated approach that involves the application of MOFs while considering environmental factors and safety concerns to develop effective MP degradation models. This review provides a framework for developing reliable photocatalytic materials with high MP removal and degradation efficiencies, thereby promoting the use of MOFs for marine plastic pollution mitigation.


Assuntos
Estruturas Metalorgânicas , Microplásticos , Poluentes Químicos da Água , Estruturas Metalorgânicas/química , Microplásticos/química , Poluentes Químicos da Água/química , Catálise , Adsorção , Fotólise , Recuperação e Remediação Ambiental/métodos
20.
Environ Res ; 263(Pt 3): 120209, 2024 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-39448012

RESUMO

Photocatalytic degradation is an effective technology for degrading water pollution that plays a significant role in environmental remediation. Ternary 2D ternary V-VI-VIIA semiconductors are ideal candidates for photocatalytic degradation of pollutants due to effective light absorption and high charge carrier mobility. In this work, high-quality SbSeI crystals were prepared using the chemical vapor transport (CVT) method and their photocatalytic degradation performance for multiple pollutants was studied. SbSeI exhibits excellent photocatalytic performance in the degradation of potassium dichromate (Cr (VI)), rhodamine B (RhB), tetracycline hydrochloride (TC-HCl) and methyl orange (MO). More than 98% of Cr (VI) and RhB can be removed after irradiation with an Xe lamp for 10 min and 40 min, respectively. The capture experiments and electron spin resonance results indicated that ·O2- plays a major role in reducing Cr (VI), while h+ plays a primary role in the degradation of MO, RhB and TC-HCl. Interestingly, the degradation rate of Cr (VI) is 1.3 times higher than that of a single pollutant system, and the degradation rate of RhB is 1.6 times higher, due to the enhanced separation and utilization of holes and electrons. The results demonstrate that SbSeI is a potential photocatalytic degradation material.

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