Photocatalyst For Degradation Research Articles

A versatile GdFeO3/NiO@g-C3N4 ternary hetero-structure photo catalyst for effective photo-degradation and adsorption of tetracycline and ciprofloxacin from wastewater

In modern times, effective removal of pharmaceutical effluents from wastewater is considered an alarming issue. In our research efforts, we have synthesized NiO and graphitic carbon nitride (g-C3N4)-decorated ternary GdFeO3/NiO@g-C3N4 heterostructure nanocomposites (NCs) for the enhanced removal of tetracycline (TC) and ciprofloxacin (CIP) antibiotics from wastewater. The GdFeO3 nanoparticles (NPs) were fabricated using a facile one-pot hydrothermal approach and the ternary NCs via an ultra-sonication approach. The structural investigation of the as-fabricated materials revealed single-phase GdFeO3 and the effective fabrication of GdFeO3/NiO@g-C3N4 NCs. Morphological analysis exhibited a round, spherical flake-like structure with heterogeneous morphology. The BET and I-V analysis exhibited improved surface and electrical features and was observed to be 43, 87, and 117 m2/g and 6.51 ×10-4 S/m, 3.67×10-2S/m, and 84.81S/m for GdFeO3 NPs, GdFeO3/NiO NPs, and GdFeO3/NiO@g-C3N4 NCs, respectively. A decline in the PL intensity was observed, which exhibited the excellent separation and stabilization of the photo-genic charge pair’s. Optical band gap energy for GdFeO3 NPs, GdFeO3/NiO NPs, and GdFeO3/NiO@g-C3N4 NCs was observed to be 2.34, 2.19, and 2.03 (eV), respectively. The GdFeO3/NiO@g-C3N4 NCs show excellent photo-degradation of CIP and TC antibiotics under visible light, achieving 92.42% and 94.23% in 45min with 4.7% and 5.1% removal via adsorption. Reusability testing exhibited only 1.3% loss in catalytic activities after 5 runs. The h+, •O2-, and the (•OH) radicals are the primarily involved in the photo-degradation of CIP and TC. The g-C3N4-based GdFeO3/NiO@g-C3N4 NCs with their highly conducting nature, the narrow band gap, improved electrical and optical properties, well-porous structures, and excellent photocatalytic activities against environmental pollutants might have advantageous applications in photo-catalysis.

G-C3N4 based Z-scheme photocatalysts for tetracycline degradation: A Comprehensive Review

Graphitic carbon nitride (g-C3N4) has garnered significant attention due to its low cost, ease of preparation, high chemical stability, and non-toxicity. Nevertheless, pristine g-C3N4 faces challenges in simultaneously achieving a broad absorption range, high stability, efficient charge separation, and strong redox capability, which hampers its practical applications. Recently, g-C3N4-based Z-scheme photocatalysts have emerged as research hotspots owing to their robust redox ability, effective charge carrier separation, and capacity to harness visible light for degradation of tetracyclines (TCs) in waters. This review delves into the fundamental photocatalysis, and application of g-C3N4-based Z-scheme photocatalysts for the degradation of TCs pollutants. The review concludes with final remarks and a concise discussion on the prospects of g-C3N4-based Z-scheme photocatalysts.

Synthesis and characterization of a novel g-C3N4/NiAl-LDH/CeO2 photocatalyst for degradation of rhodamine B

Synthesis and characterization of a novel g-C3N4/NiAl-LDH/CeO2 photocatalyst for degradation of rhodamine B

Hierarchical TiO2 nanostructures sensitized with MoS2 nanosheets: an efficient and reusable heterojunction photocatalyst for sunlight-assisted degradation of organic dye pollutants

Abstract The present study reports the synthesis, characterization, and natural sunlight-driven photocatalytic activity of a novel heterojunction photocatalyst comprised of hierarchical rutile titanium dioxide (r-TiO2) nanostructures and 1T/2H molybdenum disulfide (MoS2)nanosheets. These components were synthesized by solvothermal methods and their effective integration was achieved by using 3- aminopropyltrimethoxysilane as coupling agent. The photocatalytic activity of r-TiO2/MoS2 nanohybrid was explored for the degradation of cationic dye methylene blue (MB), and anionic dye congo red (CR) under natural sunlight. The results reveal that the sunlight-driven photocatalytic activity of pristine r-TiO2 was drastically enhanced upon sensitization with 1T/2H MoS2 nanosheets. The nanohybrid could degrade 99% MB and 98% CR within 150 min with rate constants 25.6×10−3 and 13.2×10−3 min−1respectively. The r-TiO2/MoS2 nanohybrid retained more than 85% of its catalytic activity even after four cycles of reuse. The scavenger test revealed that holes and hydroxyl radicals are mainly responsible for the degradation of MB and CR. The facile synthesis, outstanding catalytic activity under natural sunlight, and excellent recyclability make r-TiO2/MoS2 a promising heterojunction photocatalyst for the degradation of environmental pollutants from wastewater. The present study can provide new insights towards the development of efficient, economical and sustainable photocatalysts for harnessing renewable solar energy for environmental remediation applications.

Mn doping and ZnS nanoparticles modification on Bi2MoO6 to achieve an highly-efficient photocatalyst for TC degradation

Environmental pollution presents significant challenges to both human production and daily life. Photocatalytic technology offers a promising solution for environmental remediation, and Bi2MoO6 is widely recognized as an excellent visible light photocatalyst for the degradation of organic pollutants. Nevertheless, the high recombination rate of photogenerated charge carriers in Bi2MoO6 limits the number of charge carriers available for photocatalytic reactions, resulting in reduced photocatalytic efficiency. To overcome this limitation, we designed and synthesized a composite photocatalyst (30% ZnS/Mn0.08-Bi2MoO6). Mn-doped Bi2MoO6 nanosheets (Mn-Bi2MoO6) were prepared through a simple coprecipitation method, and ZnS nanoparticles were introduced to modify the surface, forming a ZnS/Mn-Bi2MoO6 composite photocatalyst. Experimental results demonstrated that the photocatalytic degradation rate of tetracycline using the 30% ZnS/Mn0.08-Bi2MoO6 composite increased 11.1 times and 3.7 times compared with pure Bi2MoO6 and ZnS, respectively. The formation of ZnS/Mn-Bi2MoO6 heterojunction was confirmed through XRD, XPS, SEM, and TEM analyses. Furthermore, photoelectrochemical measurements, including photocurrent, EIS, and PL, indicated that Mn doping and the ZnS nanoparticle modification significantly improved the separation and transfer efficiency of photogenerated charge carriers. DFT calculations and experimental results revealed the photocatalytic mechanism of the 30% ZnS/Mn0.08-Bi2MoO6 composite. This study provides valuable theoretical and technical insights into photocatalyst modification.

S-scheme3D/3D Bi0/BiOBr/P Doped g-C3 N4 with Oxygen Vacancies (Ov) for Photodegradation of Pharmaceuticals: In-situ H2O2 Production and Plasmon Induced Stability.

Complications accompanying photocatalyst stability and recombination of exciton charges in pollutants degradation has been addressed through the construction of heterojunctions, especially S-scheme heterojunction with strong and distinctive redox centres. Herein, an S-scheme BiOBr (BOR) and g-C3N4PO4 (CNPO) catalyst (BORCNPO) with oxygen vacancy (Ov) was synthesized for levofloxacin (LVX) and oxytetracycline (OTC) photodegradation under visible light. The 3D/3D BORCNPO catalyst possessed C-O-Br bridging bonds for efficient charge transfer during the fabrication of S-scheme heterojunction. In-situ H2O2 formation affirmed by potassium titanium (IV) oxalate spectrophotometric method improved the mineralization ability of BORCNPO7.5 catalyst. Bi0 surface plasmon resonance (SPR) enhanced formation and involvement of ⋅O2 - and the stability of the catalyst which increased reaction rate with increasing cycling experiments. XPS and radical trapping experiments supported the S-scheme charge transfer mechanism formation with high degradation rate of LVX which was 3 times higher than OTC degradation rate. Mineralization of pollutants and their intermediates were demonstrated with florescence excitation and emission matrix (FEEM) and quadruple time of flight high performance liquid chromatography (QTOF-HPLC). This work advances development of highly stable and efficient catalysts for photodegradation of pollutants through the formation of S-scheme heterostructure.

Tailored copper doped indium sulfide nanostructures as electrode material for supercapacitor and nano photocatalyst for dye degradation

The unique copper-doped indium sulfide nanocrystals are synthesized by a gentle hydrothermal process. XRD, FTIR, XPS, FESEM/EDX, UV-DRS, and PL were used to characterize the final samples. Copper-doped indium sulfide nanostructures can be exploited as an active catalyst in photodegradation and as an electroactive material in supercapacitors due to their distinctive architecture. The copper-doped indium sulfide catalyst exhibits 85 percent photodegradation using methylene blue dye under natural sunlight irradiation, and the electrochemical test showed a capacitance of 668 Fg−1 at 1 Ag−1 in a 2 M KOH electrolyte solution. For future generations, photocatalyst and electrode can function as more desirable materials.

A Honeycomb Layered Na2SnO3 as Novel Photocatalyst for Degradation of Rose Bengal Dye

AbstractA layered Na2SnO3 with honeycomb structure was synthesized by solid state route using sodium carbonate and tin oxide. The prepared sample was characterized by different physicochemical characterization techniques like X‐ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy dispersive X‐ray spectroscopy (EDS), X‐ray photoelectron spectroscopy (XPS), ultraviolet visible spectroscopy (UV–vis), photoluminescence spectra (PL), N2 adsorption technique (Brunauer–Emmett–Teller, electrochemical impedance spectroscopy (EIS). The photodegradation of rose bengal dye under UV light was studied. Due to honeycomb structure and high surface area of Na2SnO3, the complete degradation of rose Bengal was observed in 90 min under UV light irradiation. Results of photocatalytic dye degradation reaction demonstrated that Na2SnO3 can be employed as photocatalyst under UV light irradiation.

WO3/g-C3N4 synergistic photocatalysts for degradation and H2 production

WO3/g-C3N4 composite samples were prepared using hydrothermal method. The photocatalytic activity was assessed by photocatalytic degradation and H2 production experiments. The experimental findings suggested that WO3/g-C3N4 (1:1) degraded 95 % of the MB in 50 min and produced H2 at a rate of 712.38 μmol⸱g−1⸱h−1, which was 10 times the H2 production rate of g-C3N4. The improved photodegradation and H2 production properties could be due to the increased specific surface area, improved photogenerated carrier separation efficiency, broadened visible light absorption range, increased photocurrent density, and reduced charge transfer resistance. Meanwhile, the synergistic effect of WO3 and g-C3N4 realizes the bifunctionality of degradation and H2 production. In addition, possible reaction mechanisms of WO3/g-C3N4 composite samples in photodegradation and H2 production were proposed.

Palladium–Copper Alloy Nanoparticles Supported on Carbon Nitride Nanosheets as a Photocatalyst for Degradation of Ciprofloxacin

Palladium–Copper Alloy Nanoparticles Supported on Carbon Nitride Nanosheets as a Photocatalyst for Degradation of Ciprofloxacin

Exploring a Perovskite-type Catalyst for Diclofenac Photodegradation: a Comparative Investigation with TiO2

Exploring a Perovskite-type Catalyst for Diclofenac Photodegradation: a Comparative Investigation with TiO2

Photocatalytic degradation of Rhodamine B dye over oxygen-rich bismuth oxychloride Bi24O31Cl10 photocatalyst under UV and Visible light irradiation: Pathways and mechanism

Photocatalytic removal of organic pollutants from wastewater has recently garnered significant attention due to its environmental and ecological significance. In this study, a bismuth-rich bismuth oxychloride (Bi24O31Cl10) was synthesized using a single-step solid-state reaction and applied as a photocatalyst for the degradation of rhodamine B in aqueous solution. The photocatalyst was prepared through an eco-friendly solid-state method by mixing bismuth oxide (Bi2O3) and bismuth oxychloride (BiOCl), followed by direct annealing at 600 °C. The synthesized material was characterized through various techniques, including X-ray diffraction (XRD), Fourier-transform infrared (FTIR), Raman spectroscopy, scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET) surface area analysis, energy dispersive X-ray spectroscopy (EDS), diffuse reflectance, UV–Visible, and photoluminescence (PL) spectroscopies. The electronic structure of the Bi24O31Cl10 bulk material was analyzed using Density Functional Theory (DFT).Rietveld refinement confirmed the formation of a pure monoclinic Bi24O31Cl10 phase with the space group P2/c, and the XRD patterns indicated well-crystallized material. SEM revealed micron-sized crystallites, while BET surface area analysis showed a value of 22.546 m²/g, suggesting that a larger surface area could enhance photocatalytic performance. The band gap of the material was determined to be 2.88 eV, with an absorption edge at 430 nm, indicating a promising response to visible light.The photocatalytic activity of Bi24O31Cl10 was demonstrated by the degradation of rhodamine B (RhB), with complete degradation achieved in 90 min under UV light. Under visible light, 98 % degradation efficiency was reached after 180 min. Kinetic studies showed that the degradation followed a pseudo-first-order model. Optimal conditions for maximum degradation were found at a solution pH of 5, a catalyst concentration of 1 g/L, and a dye concentration of 5 mg/L. Remarkably, the photocatalyst exhibited excellent reusability, maintaining high efficiency over five cycles, with only a slight decrease from 100 % to 90 %.Trapping experiments identified that reactive species such as superoxide radicals (∙O2−) and hydroxyl radicals (∙OH) played key roles in the photocatalytic process. The possible reaction mechanism was proposed, and degradation products were monitored using liquid chromatography-mass spectrometry (LC-MS), allowing for the elucidation of the degradation pathways of RhB. Additionally, the photocatalyst's effectiveness was tested on Methyl Orange (MO) and Methylene Blue (MB), achieving nearly 100 % degradation for MO and 41 % for MB under UV light. This research highlights the significant potential of Bi24O31Cl10 as a photocatalyst for dye degradation in wastewater treatment.

Magnetically retrievable Nb2O5/CoFe2O4 photocatalysts for degradation of crystal violet dye pollutant under solar irradiation

Electrochemical oxidations of complex toxic dyes have been widely investigated on metal–organic-framework, which are often limited by high energy demand or deactivation of organic support. Here, the potential application of a magnetically retrievable solar-driven nanocomposite of Nb2O5-CoFe2O4 for removing crystal violet was explored and compared under simulated solar radiation (60.82 mW/cm2) or darkness. In the synthesized composite, Nb2O5 exists as a dispersed phase on CoFe2O4, forming a core–shell structure. Both the optical and magnetic behaviour of Nb2O5-CoFe2O4 were extensively investigated to optimize their photocatalytic applications in the removal of crystal violet.The nanocomposite was strongly ferromagnetic even after loading Nb2O5 on cobalt ferrite. The photocatalytic performance of the composites showed a positive relationship with the Nb2O5 content, where optimum degradation was observed with 50 % Nb2O5-CoFe2O4. The ferromagnetic property was exploited to retrieve the catalyst from the water after the purification process. This study demonstrates the facile method for the novel Nb2O5-CoFe2O4 synthesis and elucidates its high potential in sustainable remediation of complex toxic dyes using solar energy and as reusable magnetic recovery in aqueous systems. Also, 50 % Nb2O5-CoFe2O4 has been implemented inwater purification processes and pollutant degradation, thereby definitely amplifying the prospects for sustainable development of this research work.

BiVO4/sulfur-doped g-C3N4 nanocomposite as photocatalyst for degradation of ciprofloxacin under visible light irradiation

In recent years, the use of antibiotics has greatly increased, which has caused environmental pollution. We offer a photocatalyst based on BiVO4/sulfur-doped g-C3N4 nanocomposite, which was made by a one-step thermal condensation method from thiourea and bismuth vanadate to degradate ciprofloxacin (CIP). The BiVO4/sulfur-doped g-C3N4 photocatalyst was analyzed by certain techniques including XRD, FTIR, BET, FESEM, EDX, TEM, DRS, photoluminesence, and Mott-Schottky to determine various physicochemical properties. The photocatalytic degradation of CIP, as a model pollutant, under visible LED light irradiation was tested to investigate the catalytic performance of nanocomposite. Response Surface Methodology (RSM) was employed to optimize operational parameters, including photocatalyst dosage (50–150 mg), CIP concentration (10–30 mg/L), initial pH of the solution (3–11), and irradiation time (12–120 min). The BiVO4/sulfur-doped g-C3N4 nanocomposite, with a narrow bandgap of 2.15 eV, exhibited exceptional photocatalytic performance in degrading CIP. The optimal conditions for CIP removal were photocatalyst dosage of 120.9 mg, CIP concentration of 10 mg/L, and initial solution pH of 3, resulting in 93.5 % removal efficiency after 105 min of irradiation. The photocatalytic degradation kinetics of CIP followed a pseudo-first-order model with a rate constant (K) of −0.0221 L/min, indicating rapid degradation process. The photocatalyst maintained excellent performance after 5 reuses, with only a 3 % reduction in efficiency. XRD analysis confirmed the structural stability of the nanocomposite after reuse.

Ti3+ self-doped TiO2 nanoparticles immobilized on self-pillared pentasil zeolite nanosheets: An efficient visible-light-driven degradation photocatalyst

Ti3+ defective TiO2 nanoparticles (TiO2-NPs) were synthesized through slow hydrolyzation of tetrabutyl titanate and low-temperature annealing, followed by loading on self-pillared pentasil (SPP) zeolite nanosheets to construct a TiO2/zeolite hybrid composite by solid-state dispersion. The obtained TiO2-NPs/SPP composite exhibited a distinct red-shift in the UV–vis absorption spectrum and a significantly reduced band gap due to the introduced Ti3+ defects and the consequent oxygen vacancies (VO), leading to an enhanced visible-light responsivity. The diverse porosity and house-of-cards nanosheet morphology of the SPP support not only promoted the efficient loading and stable immobilization of TiO2-NPs nanoparicles through micropore migration and surface adhesion but also endowed the adsorbability to the TiO2-NPs/SPP composite. The adsorptive photodegradation of methylene blue (MB) was used to evaluated the photocatalytic performance of TiO2-NPs/SPP, and a 95.6 % degradation rate of MB was observed after 3 h illumination with visible-light. The adsorptive effect strongly promoted the accessibility of MB molecules to the active TiO2 species, leading to a remarkable enhancement in degradation efficiency. Moreover, a superior recyclability embodied in the retention of 96.4 % photocatalytic activity after three regeneration cycles indicated the TiO2-NPs/SPP composite to be practical for water pollutant degradation.

Synthesis, characterization and correlation studies on the Ni–Zn–Mn ferrite as a photocatalyst

Samples of Ni0.3Zn0.7−xMnxFe2O4 (x = 0, 0.15, 0.25, 0.35, 0.45, 0.55) nanoparticles (NPs) were synthesized by auto-combustion flash method. These ferrites were used as catalysts for photodegradation of methylene blue (MB) dye utilizing visible light energy. Structural analysis was carried out using the X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy, while nanoparticle dimensions were elucidated through transmission electron microscopy (TEM). The magnetic and optical behaviours were unveiled via vibrating sample magnetometer and UV–VIS spectroscopy, respectively. The XRD outcomes established the presence of a cubic spinel-type structure for the studied ferrite samples. The FTIR spectra unveiled two absorption characteristic bands of the spinel ferrite. TEM images revealed nanoscale dimensions of ferrite NPs with the range from 21.1 to 51.8 nm. The optical features exhibited an indirect band gap energy spanning from 4.25 to 4.36 eV. Magnetization behaviour displayed a sinusoidal trend corresponding to varying Mn concentrations. The ferrite NPs catalyst (10 mg) yield photodegradation efficiency ranged from 22.8 to 33.9% for 100 ml MB dye solution after 120 min of light irradiation. The effects of dye concentration and catalyst dose on the degradation efficiency were examined using the Ni0.3Zn0.35Mn0.35Fe2O4 catalyst with highest degradation (= 33.9%). On the other hand, the dependence of the degradation efficiency on the structure, morphological, magnetic and optical properties of the photocatalyst was investigated. The findings of this study underscore the potential of the prepared ferrite nanoparticles for advanced applications in environmental restoration.Graphical abstract

A new Zn(II)-based 3D MOF with PCU-like topology: Potent photocatalyst for nitrofurazone antibiotic degradation

Metal-organic frameworks (MOFs), a sub-class of coordination polymers, are versatile multidimensional materials that have the potential to serve as photocatalysts for the degradation of antibiotics found in wastewater. Herein, a new three dimensional (3D) Zn(II)-based MOF [Zn(TA)(bpyp)·3H2O] (1) (bypy = 2,5-bis(pyrid-4-yl)pyridine; H2TA = terephthalic acid) has been synthesized and characterized. The MOF 1 shows a 3D PCU-like topology and exhibits semiconducting properties with band gap of 3.34 eV and hence used as a photocatalyst for photodegradation of antibiotics viz. sulfasalazine (SLA), nitrofurazone (NFZ) and furazolidone (FZD) under simulated UV light irradiation. The photocatalytic results suggest that MOF 1 exhibits best photocatalytic activity for the photodegradation of nitrofurazone (NFZ) in 60 min time-span. The effects of initial concentration of NFZ, and photocatalyst dosage have been monitored for the photocatalytic performance of 1. The radical trapping experiments suggest that (holes) h+ and superoxide radical (O2·−) collectively catalyzes the photodecomposition of antibiotics. The possible mechanism for the antibiotic degradation by photocatalyst 1 have been proposed by integrating experiment with density of states (DOS) calculations and Hirshfeld surface analysis.

Synergistic effects of Co-Mn co-doping on the structural and optical properties of TiO2 nanospheres: Dual functions for DSSC photoanodes and degradation photocatalyst

Synthesizing direct solar irradiance-responsive nanomaterial capable of serving as an efficient photoanode for dye-sensitized solar cells (DSSCs) and active photocatalysts for organic pollutant elimination poses a formidable challenge. This study focused on the synthesis of cobalt and manganese co-doped titanium dioxide (TiO2) nanoparticles via sol-gel technique, enhancing their efficacy in both the DSSCs and methylene blue (MB) dye degradation. X-ray diffraction and Raman analysis confirm the existence of a tetragonal crystal structure with the anatase phase of TiO2, while XPS analysis verifies the successful integration of cobalt and manganese ions into the host lattices. BET analysis has confirmed that Co, Mn co-doped TiO2 exhibits a higher pore volume and specific surface area compared to the undoped TiO2 material. FESEM and HR-TEM reveals spherical shape morphology and EDS mapping confirms the purity of synthesized nanoparticles. Moreover, Co-Mn co-doped TiO2 nanoparticles exhibits a shift in the optical absorption edge towards the visible spectrum in UV-DRS analysis. PL analysis suggests a diminished electron-hole recombination within the doped and co-doped sample. Electrochemical impedance spectroscopy demonstrates improved charge transfer properties. DSSCs employing the co-doped TiO2 exhibit significantly enhanced power conversion efficiency (4.99 %) compared to bare TiO2 (2.03 %), cobalt-doped (2.61 %), and manganese-doped TiO2 (3.97 %). Additionally, it demonstrates exceptional photocatalytic activity, with 87.83 % (Co-Mn co-doped TiO2) degradation efficiency with a lesser time extent for the methylene blue dye degradation. These findings underscore the potential of Co-Mn co-doped TiO2 for addressing dual challenges in renewable energy (DSSC) and environmental remediation (Pollutant removal).

Synthesis of iron phthalocyanine/CeO2 Z-scheme nanocomposites as efficient photocatalysts for degradation of 2,4-dichlorophenol.

Modulating the photogenerated electrons of CeO2 to activate O2 and efficiently photocatalytic degradation of chlorophenols is a highly desired goal. Herein, we have successfully fabricated an FePc/CeO2 heterojunction through H-bond induced assembly. The photocatalytic degradation of 2,4-DCP by the amount-optimized FePc/CeO2 nanocomposite was improved by 3 times compared with that by pure CeO2. By means of electron paramagnetic resonance (EPR) and single wavelength photocurrent spectroscopy, it is confirmed that the excellent photocatalytic performance is mainly attributed to the formation of the Z-scheme heterojunction, which promotes charge separation and transfer, and the introduction of FePc broadens the visible light absorption range of the heterojunction. Moreover, O2 temperature-programmed-desorbed curves and electrochemical O2 reduction measurement results demonstrate that the single Fe-N4(II) site in FePc is more conducive to promoting O2 activation than that of other metal phthalocyanines. Based on in situ FT-IR and liquid chromatography-tandem mass spectrometry (LC-MS/MS), a possible reaction pathway of 2,4-DCP degradation was proposed. This study provides a novel strategy for preparing CeO2 based Z-scheme heterojunctions with abundant monoatomic sites for pollutant degradation.

Facile synthesis of NH2-MIL-53(Al)@BiOBr@CQDs ternary heterostructure photocatalyst for degradation of ciprofloxacin in water

The construction of ternary heterojunction photocatalysts can achieve multi-gradient transfer of charges and accurate control the position of photogenerated electrons which has received increasing attention. In this paper, NH2-MIL-53(Al)@BiOBr@CQDs-10 % (ABCQDs-10 %) was prepared via a facile hydrothermal and chemical synthesis processes. Three-dimensional serration of NH2-MIL-53(Al) as a platform for irregular BiOBr nanosheets, CQDs promote interfacial contact and act as electron transport channels between BiOBr and NH2-MIL-53(Al) and constitute Z-type heterojunctions with high redox properties. ABCQDs-10 % shows the best photocatalytic removal efficiency (94.24 %) of CIP, the reaction rate constants (0.045 min−1) were 1.2 and 64 times higher than BiOBr and NH2-MIL-53(Al), respectively. The excellent degradation performance is attributed to the construction of Z-type heterojunction of NH2-MIL-53(Al)@BiOBr@CQDs which improve electron-hole separation and transfer efficiency. The main active species was •O2-. The photocatalytic activity of ABCQDs-10 % had not obvious loss after cycle experiments and the crystal structure had no significant changes, means high stable photocatalytic activity.