Peroxymonosulfate(PMS)-assisted visible-light photocatalytic degradation of organic pollutants using graphitic carbon nitride(g-C_(3)N_(4))presents a promising and environmentally friendly approach.However,pristine g-...Peroxymonosulfate(PMS)-assisted visible-light photocatalytic degradation of organic pollutants using graphitic carbon nitride(g-C_(3)N_(4))presents a promising and environmentally friendly approach.However,pristine g-C_(3)N_(4) suffers from limited visible-light absorption and low charge-carrier mobility.In this study,a phosphorus-doped tubular carbon nitride(5P-TCN)was synthesized via a precursor self-assembly method using phosphoric acid and melamine as raw materials,eliminating the need for organic solvents or templates.The 5P-TCN catalyst demonstrated enhanced visible-light absorption,improved charge transfer capability,and a 5.25-fold increase in specific surface area(31.092 m^(2)/g),which provided abundant active sites to efficiently drive the PMS-assisted photocatalytic reaction.The 5P-TCN/vis/PMS system exhibited exceptional degradation performance for organic pollutants across a broad pH range(3–9),achieving over 92%degradation of Rhodamine B(RhB)within 15 min.Notably,the system retained>98%RhB degradation efficiency after three consecutive operational cycles,demonstrating robust operational stability and reusability.Moreover,key parameters influencing,active radi-cals,degradation pathways,and potential mechanisms for RhB degradation were systematically investigated.This work proposes a green and cost-effective strategy for developing high-efficiency photocatalysts,while demon-strating the exceptional capability of a PMS-assisted photocatalytic system for rapid degradation of RhB.展开更多
Cobalt-based catalysts were regarded as highly effective for pollutant degradation through peroxymono-sulfate activation.Nevertheless,conventional synthesis methods for cobalt-based catalysts were associ-ated with iss...Cobalt-based catalysts were regarded as highly effective for pollutant degradation through peroxymono-sulfate activation.Nevertheless,conventional synthesis methods for cobalt-based catalysts were associ-ated with issues of cobalt ion leakage,which posed a risk of secondary environmental contamination.Addressing this issue,a novel cobalt-based catalyst,CoS nanoparticles,was biosynthesized by Shewanella algae and designated as SA@CoS.SA@CoS,a nanoflower coated with proteins/peptides,contained a sig-nificant number of sulfur vacancies.Compared to chemically synthesized CoS,SA@CoS exhibited lower cobalt ion release(0.13 mg/L)and higher catalytic activity.Based on this,SA@CoS was employed to de-grade Rhodamine B(RhB)and tetracycline(TC)by activating peroxymonosulfate.The results indicated that the degradation efficiencies of RhB and TC could reach 99.9%and 90.5%within 10 min,respec-tively.Further analyses revealed that both radical(·O_(2)^(-),·OH and SO_(4)^(·-))and non-radical(_(1)O_(2))pathways were involved in the degradation of RhB and TC,with the non-radical pathway dominating the degra-dation process.This work not only offered a facile approach for the biosynthesis of stable cobalt-based catalysts,but also underscored the immense potential of biogenic nano-catalysts in the realm of environ-mental remediation.展开更多
The regulation of peroxymonosulfate(PMS)activation by constructing oxygen vacancy and heterogeneous interface catalytic is crucial towards the oxidation of refractory pollutants still remains a major hurdle.This work ...The regulation of peroxymonosulfate(PMS)activation by constructing oxygen vacancy and heterogeneous interface catalytic is crucial towards the oxidation of refractory pollutants still remains a major hurdle.This work demonstrates a strategy to constructed ethylene glycol(EG)well-coupled S-scheme heterojunction of NiFe_(2)O_(4-x)/NiS with oxygen vacancy(VO)-modified to efficiently achieve pollutant removal by activating PMS through photoexcitation,a 99%PMS decomposition efficiency is achieved.Photoassisted Kelvin probe force microscopy and in-situ electron spin resonance verify the establishment of a charge-transfer pathway consistent in NiFe_(2)O_(4-x)/NiS with an S-scheme heterojunction,which dramatically provides abundant active sites and distinct charge transport pathway for organic pollutant oxidation.The S-scheme NiFe_(2)O_(4-x)/NiS heterojunction in the photo-Fenton-like system exhibited significantly enhanced degradation rate(0.15 min^(-1))at a low PMS dosage of 0.1 g/L,which is 19 times greater than that of the pristine NiS(0.0077 min^(-1)).Density functional theory calculations confirmed that VO in NiFe_(2)O_(4-x)/NiS efficiently promoted PMS adsorption and lowered the energy barrier for electron transfer.Moreover,in-situ experiments and experimental evidence offer mechanistic insights into the PMS activation through photoexcitation,unraveling a dual-pathway activation mechanism involving reduction and oxidation processes over NiFe_(2)O_(4-x)/NiS during the reaction.This work emphasizes the potential of vacancy engineering synergistic S-scheme heterojunction in developing efficient catalysts for regulating PMS activation,providing a promising solution the cost-effective and efficient treatment of organic wastewater.展开更多
The influence of electronic structure on the performance of catalysts for peroxymonosulfate(PMS)activation remains ambiguous.In this study,the 3d electron configuration of Fe(Ⅲ)in AgFeO_(2) was atomically regulated u...The influence of electronic structure on the performance of catalysts for peroxymonosulfate(PMS)activation remains ambiguous.In this study,the 3d electron configuration of Fe(Ⅲ)in AgFeO_(2) was atomically regulated using cobalt doping.The amount of PMS adsorbed and the catalytic performance were positively correlated with the total effective magnetic moment and the ratios of high-spin Fe(Ⅲ)and eg filling within the catalysts.These 3d electron regulations favor PMS adsorption and electron transfer owing to the lower PMS adsorption energy,increased electronic states near the Fermi level,and reduced dz^(2) orbital occupancy.Benefiting from fine tailoring of the electron configuration,the AgFe_(0.80)Co_(0.20)O_(2) catalyst exhibited outstanding catalytic PMS activation and favorable application potential,achieving efficient pharmaceutical wastewater treatment and more than 80%ofloxacin removal after 72 h of continuous-flow operation.Notably,this study offers a comprehensive understanding for the influence mechanism of electronic structure regulation on PMS activation,providing design guidance for the development of efficient heterogeneous Fenton-like catalytic systems.展开更多
Fenton-like technology based on peroxymonosulfate activation has shown great potential in refractory organics degradation.In this work,single Fe atom catalysts were synthesized through facile ball milling and exhibite...Fenton-like technology based on peroxymonosulfate activation has shown great potential in refractory organics degradation.In this work,single Fe atom catalysts were synthesized through facile ball milling and exhibited very high performance in peroxymonosulfate activation.The Fe single-atom filled an N vacancy on the triazine ring edge of C_(3)N_(4),as confirmed through X-ray absorption fine structure,density functional calculation and elec-tron paramagnetic resonance.The SAFe_(0.4)–C_(3)N_(4)/PMS system could completely remove phenol(20 mg/L)within 10 min and its first-order kinetic constant was 12.3 times that of the Fe_(3)O_(4)/PMS system.Under different ini-tial pH levels and in various anionic environments,SAFe_(0.4)–C_(3)N_(4) still demonstrated excellent catalytic activity,achieving a removal rate of over 90%for phenol within 12 min.In addition,SAFe_(0.4)–C_(3)N_(4) exhibited outstanding selectivity in reaction systems with different pollutants,showing excellent degradation effects on electron-rich pollutants only.Hydroxyl radicals(•OH),singlet oxygen(1O_(2))and high-valent iron oxide(Fe(Ⅳ)=O)were de-tected in the SAFe_(0.4)–C_(3)N_(4)/PMS system through free radical capture experiments.Further experiments on the quenching of active species and a methyl phenyl sulfoxide probe confirmed that 1O_(2) and Fe(Ⅳ)=O played dom-inant roles.Additionally,the change in the current response after adding PMS and phenol in succession proved that a direct electron transfer path between organic matter and the catalyst surface was unlikely to exist in the SAFe_(0.4)–C_(3)N_(4)/PMS/Phenol degradation system.This study provides a new demonstration of the catalytic mech-anism of single-atom catalysts.展开更多
Nonradical reaction driven by peroxymonosulfate(PMS)based advanced oxidation pro-cesses has drawn widespread attention in water treatment due to their inherent advantages,but the degradation behavior and mechanism of ...Nonradical reaction driven by peroxymonosulfate(PMS)based advanced oxidation pro-cesses has drawn widespread attention in water treatment due to their inherent advantages,but the degradation behavior and mechanism of organic pollutants are still unclear.In this study,the performance,intermediates,mechanism and toxicity of tetracycline(TC)degra-dation were thoroughly examined in the constructed magnetic nitrogen-doped porous car-bon/peroxymonosulfate(Co-N/C-PMS)system.The results showed that 85.4%of TC could be removed within 15 min when Co-N/C and PMS was simultaneously added and the degra-dation rate was enhanced by 3.4 and 14.7 folds compared with Co-N/C or PMS alone,re-spectively.Moreover,the performance of Co-N/C was superior to that of most previously reported catalysts.Many lines of evidence indicated that Co-N/C-PMS system was a singlet oxygen-dominated nonradical reaction,which was less interfered by pH and water compo-nents,and displayed high adaptability to actual water bodies.Subsequently,the degrada-tion process was elaborated on the basis of three-dimensional excitation-emission matrix spectra and liquid chromatography-mass spectrometry.At last,the toxicity of treated TC was greatly reduced by using microalgae Coelastrella sp.as ecological indicator.This study provides a promising approach based on singlet oxygen-dominated nonradical reaction for eliminating TC in water treatment.展开更多
Excitation of metal-free graphitic carbon nitride(g-C3N4) under visible light can successfully achieve efficient activation of peroxymonosulfate(PMS). Synergistic effects and involved mechanism were systematically inv...Excitation of metal-free graphitic carbon nitride(g-C3N4) under visible light can successfully achieve efficient activation of peroxymonosulfate(PMS). Synergistic effects and involved mechanism were systematically investigated using a light-inert endocrine disrupting compound, dimethyl phthalate(DMP), as the target pollutant. Under visible light irradiation, DMP could not be degraded by direct g-C3 N4-mediated photocatalysis, while in the presence of PMS, the dominant radicals were converted from ·O2 to SO4·– and ·OH, resulting in effective DMP degradation and mineralization. Results showed that higher dosage of PMS or g-C3 N4 could increase the activation amount of PMS and corresponding DMP degradation efficiency, but the latter approach was more productive in terms of making the most of PMS. High DMP concentration hindered effective contact between PMS and g-C3 N4, but could provide efficient use of PMS. Higher DMP degradation efficiency was achieved at p H lower than the point of zero charge(5.4). Based on intermediates identification, the DMP degradation was found mainly through radical attack(·OH and SO4·–) of the benzene ring and oxidation of the aliphatic chains.展开更多
Peroxymonosulfate(PMS)activation in heterogeneous processes is a promising water treatment technology.Nevertheless,the high energy consumption and low efficiency during the reaction are ineluctable,due to electron cyc...Peroxymonosulfate(PMS)activation in heterogeneous processes is a promising water treatment technology.Nevertheless,the high energy consumption and low efficiency during the reaction are ineluctable,due to electron cycling rate limitation.Herein,a new strategy is proposed based on a quantum dots(QDs)/PMS system.Co-ZnS QDs are synthesized by a water phase coprecipitation method.The inequivalent lattice-doping of Co for Zn leads to the generation of surface sulfur vacancies(SVs),which modulates the surface of the catalyst to form an electronic nonequilibrium surface.Astonishingly,the plasticizer micropollutants can be completely degraded within only tens of seconds in the Co-Zn S QDs/PMS system due to this type of surface modulation.The interfacial reaction mechanism is revealed that pollutants tend to be adsorbed on the cobalt metal sites as the electron donors,where the internal electrons of pollutants are captured by the metal species and transferred to the surface SVs.Meanwhile,PMS adsorbed on the SVs is reduced to radicals by capturing electrons,achieving effective electron recovery.Dissolved oxygen(DO)molecules are also easily attracted to catalyst defects and are reduced to O_(2)^(·-),further promoting the degradation of pollutants.展开更多
An environmentally friendly Mn‐oxide‐supported metal‐organic framework(MOF),Mn3O4/ZIF‐8,was successfully prepared using a facile solvothermal method,with a formation mechanism proposed.The composite was characteri...An environmentally friendly Mn‐oxide‐supported metal‐organic framework(MOF),Mn3O4/ZIF‐8,was successfully prepared using a facile solvothermal method,with a formation mechanism proposed.The composite was characterized using X‐ray diffraction,scanning electron microscopy,transmission electron microscopy,X‐ray photoelectron microscopy,and Fourier‐transform infrared spectroscopy.After characterization,the MOF was used to activate peroxymonosulfate(PMS)for degradation of the refractory pollutant rhodamine B(RhB)in water.The composite prepared at a0.5:1mass ratio of Mn3O4to ZIF‐8possessed the highest catalytic activity with negligible Mn leaching.The maximum RhB degradation of approximately98%was achieved at0.4g/L0.5‐Mn/ZIF‐120,0.3g/L PMS,and10mg/L initial RhB concentration at a reaction temperature of23°C.The RhB degradation followed first‐order kinetics and was accelerated with increased0.5‐Mn/ZIF‐120and PMS dosages,decreased initial RhB concentration,and increased reaction temperature.Moreover,quenching tests indicated that?OH was the predominant radical involved in the RhB degradation;the?OH mainly originated from SO4??and,hence,PMS.Mn3O4/ZIF‐8also displayed good reusability for RhB degradation in the presence of PMS over five runs,with a RhB degradation efficiency of more than96%and Mn leaching of less than5%for each run.Based on these findings,a RhB degradation mechanism was proposed.展开更多
The widely used carbamazepine(CBZ)is one of the most persistent pharmaceuticals and suffers insufficient removal efficiency by conventional wastewater treatment.A synthesized Co-based perovskite(LaCoO3)was used to act...The widely used carbamazepine(CBZ)is one of the most persistent pharmaceuticals and suffers insufficient removal efficiency by conventional wastewater treatment.A synthesized Co-based perovskite(LaCoO3)was used to activate peroxymonosulfate(PMS)in order to degrade CBZ.Results showed that LaCoO3 exhibited an excellent performance in PMS activation and CBZ degradation at neutral pH,with low cobalt leaching.The results of FT-IR and XPS verified the high structurally and chemically stability of LaCoO3 in PMS activation.Electron spin resonance(ESR)analysis suggested the generation of radical species,such as sulfate radicals(SO4·-)and hydroxyl radicals(·OH).Radical quenching experiments further revealed the responsibility of SO4·-as the dominant oxidant for CBZ oxidation.Ten products were detected via the oxidation of CBZ,with the olefinic double bond attacked by SO4·-as the initial step.Hydroxylation,hydrolysis,cyclization and dehydration were involved along the transformation of CBZ.The toxicity of CBZ solution was significantly reduced after treating by PMS/LaCoO3.展开更多
In this study,Fe_(2)O_(3)/Mn_(2)O_(3) composite was synthesized by a facile two-step technique,and several methods were carried out to characterize it.Then,the decomposition experiments of tartrazine(TTZ),a kind of re...In this study,Fe_(2)O_(3)/Mn_(2)O_(3) composite was synthesized by a facile two-step technique,and several methods were carried out to characterize it.Then,the decomposition experiments of tartrazine(TTZ),a kind of refractory o rganic pollutant,were conducted under various enviro nmental condition to detect the catalyst performance,such as reaction system,the dosage of catalyst,peroxymonosulfate(PMS)concentration,initial pH,different natural water substances.The results exhibited that Fe_(2)O_(3)/Mn_(2)O_(3) composite with the mole rate 2:3 had the best PMS activation performance and the removal efficiency was 97.3%within 30 min.Besides,the optimum degradation conditions of TTZ we re also discussed,that is catalyst dosage(0.6 g/L),PMS concentration(0.8 g/L)and the initial pH 11.In addition,proved by the natural water substances adding experiments,HPO_(4)^(2)-,HCO_(3)^-,NO_(3)^-and NOM(nature organic matter)could slow down the experiments progressing,but Cl^-could boost it.Then inhibitor experiments indicated both the HO^·and SO_(4)^·-played a vital role in the experiments.Reusability and ions leaching experiments as well as the used catalyst physical characte rization images exhibited the excellent stability and cyclicity of the Fe_(2)O_(3)/Mn_(2)O_(3) composite.Finally,based on the XPS(X-ray photoelectro n spectro scopy)and the experiments results,the possible mechanism of TTZ degradation was proposed.This system might provide a novel thought for the decomposition of refractory organic pollutant and had potential in promotion of actual sewage treatment technology.展开更多
Metal-based perovskite oxides have contributed significantly to the advanced oxidation processes(AOPs)due to their diverse active sites and excellent compositional/structural flexibility.In this study,we specially des...Metal-based perovskite oxides have contributed significantly to the advanced oxidation processes(AOPs)due to their diverse active sites and excellent compositional/structural flexibility.In this study,we specially designed a perovskite oxide with abundant oxygen vacancies,SrCo_(0.8)Fe_(0.2)O_(3)(SCF),and firstly applied it as a catalyst in peroxymonosulfate(PMS) activation towards organic pollutants degradation.The result revealed that the prepared SCF catalyst exhibited excellent performance on organic compounds degradation.Besides,SCF showed much better activity than La_(0.5)Sr_(0.5)Co_(0.8)Fe_(0.2)O_(3)(LSCF) in terms of reaction rate and stability for the degradation of the organic compounds.Based on the analysis of scanning electron microscope,transmission electron microscope,X-ray diffraction,N_(2) adsorption-desorption,X-ray photoelectron spectroscopy and electron paramagnetic resonance,it was confirmed that the perovskite catalysts with high content of Sr doping at A-site could effectively create a defect-rich surface and optimize its physicochemical properties,which was responsible for the excellent heterogeneous catalytic activity of SCF.SCF can generate three highly active species:~1 O_(2),SO_(4)^(-)· and ·OH in PMS activation,revealing the degradation process of organic compounds was a coupled multiple active species in both radical and nonradical pathway.Moreover,it was mainly in a radical pathway in the degradation through PMS activation on SCF and SO_(4)^(-)· radicals produced were the dominant species in SCF/PMS system.This study demonstrated that perovskite-type catalysts could enrich OVs efficiently by doping strategy and regulate the PMS activation towards sulfate radical-based AOPs.展开更多
Hollow microsphere structure cobalt hydroxide(h-Co(OH)2) was synthesized via an optimized solvothermal-hydrothermal process and applied to activate peroxymonosulfate(PMS) for degradation of a typical pharmaceutically ...Hollow microsphere structure cobalt hydroxide(h-Co(OH)2) was synthesized via an optimized solvothermal-hydrothermal process and applied to activate peroxymonosulfate(PMS) for degradation of a typical pharmaceutically active compound,ibuprofen(IBP).The material characterizations confirmed the presence of the microscale hollow spheres with thin nanosheets shell in h-Co(OH)2,and the crystalline phase was assigned to a-Co(OH)2.h-Co(OH)2 could efficiently activate PMS for radicals production,and 98.6% of IBP was degraded at 10 min.The activation of PMS by h-Co(OH)2 was a pHindependent process,and pH 7 was the optimum condition for the activation-degradation system.Scavenger quenching test indicated that the sulfate radical(SO4^·-) was the primary reactive oxygen species for IBP degradation,which contributed to 75.7%.Fukui index(f^-) based on density functional theory(DFT) calculation predicted the active sites of IBP molecule for SO4^·- attack,and then IBP degradation pathway was proposed by means of intermediates identification and theoretical calculation.The developed hollow Co(OH)2 used to efficiently activate PMS is promising and innovative alternative for organic contaminants removal from water and wastewater.展开更多
The Z-scheme heterostructure for photocatalyst can effectively prolong the lifetime of photogenerated carriers and retain a higher conduction/valence band position,promoting the synergistic coupling of photocatalysis ...The Z-scheme heterostructure for photocatalyst can effectively prolong the lifetime of photogenerated carriers and retain a higher conduction/valence band position,promoting the synergistic coupling of photocatalysis and peroxymonosulfate(PMS) activation.In order to fully utilize the luminous energy and realize the efficient activation of PMS,this work achieved successful construction of NiCo_(2)O_(4)/BiOCl/Bi_(24)O_(31)Br_(10) ternary Z-scheme heterojunction by simultaneously synthesizing BiOCl and NiCo_(2)O_(4) with NiCl_(2) and CoCl_(2) as the precursors.The intercalated BiOCl could serve as a carrier migration ladder to further achieve the spatial separation of electron-hole pairs,so that the oxidation and reduction processes separately occurred in different regions.Compared with the reported catalysts,the as-prepared composites exhibited the enhanced removal efficiency for tetracycline hydrochloride(TCH) in the visible light/PMS system,with a degradation efficiency of 85.30%in 2 min,and possessed good stability.Z-scheme heterojunction was shown to be beneficial for maximizing the superiority of photo-assisted Fenton-like reaction system.The experimental and characterization results confirmed that both non-radicals(^(1)O_(2)) and radicals(SO_(5)^(·-) and SO_(4)^(·-)) were involved in the reaction process and the SO_(5)^(·-)generated by the oxidation of PMS played a crucial role in the TCH degradation.The possible reaction mechanism was finally proposed.This study provided new insight into the Z-scheme heterostructure to promote the photo-assisted Fenton-like reaction.展开更多
β-lactam antibiotics in aquatic environment have severely damaged ecological stability and caused a series of environmental pollution problems to be solved urgently.Herein,a novel composite photocatalyst prepared by ...β-lactam antibiotics in aquatic environment have severely damaged ecological stability and caused a series of environmental pollution problems to be solved urgently.Herein,a novel composite photocatalyst prepared by loading carbon dots(CDs)onto rod-like CoFe_(2)O_(4)(CFO),which can effectively degrade amoxicillin(AMX)by photocata lytic/peroxy mono sulfate(PMS)activation under visible light irradiation.The degradation results exhibits that the optimal degradation efficiency with 97.5%within 80 min is achievd by the CDs-CFO-5 composite.Such enhanced activity is ascribed to the introduction of CDs that effectively improves the separation efficiency of photogenerated electron pairs and creates new active sites as electron bridges that improve the photocata lytic performance.More importantly,a strong synergistic between CDs and photo-induced electrons generated from CFO can further activiate PMS to provide more SO4-·and·OH radicals for boosting the degradation ability towards AMX.The present study aims to elucidate positive role of CDs in photocata lytic/peroxy monosulfate activation during the degradation reaction.展开更多
Morphology and dispersity are key factors for activating peroxymonosulfate(PMS).In this study,we designed a recyclable open-type NiCo_(2)O_(4) hollow microsphere via a simple hydrothermal method with the assistance of...Morphology and dispersity are key factors for activating peroxymonosulfate(PMS).In this study,we designed a recyclable open-type NiCo_(2)O_(4) hollow microsphere via a simple hydrothermal method with the assistance of an NH_(3) vesicle.The physical structure and chemical properties were characterized using techniques such as scanning electron microscope(SEM),transmission electron microscope(TEM),X-ray diffraction(XRD),N2 adsorption and X-ray photoelectron spectroscopy(XPS).The test results confirm that the inner and outer surfaces of open-type NiCo_(2)O_(4) hollow-sphere can be efficiently utilized because of the hole on the surface of the catalyst,which can minimize the diffusion resistance of the reactants and products.Under optimized conditions,the total orga nic carbon(TOC) removal efficiency of rhodamine B(RhB) can reach up to 80% in 40 min,which is almost 50% shorter than the reported values.The reactive radicals were identified and the proposed reaction mechanism was well described.Moreover,the disturbances of HCO_(3)^(-),NO_(3)^(-),Cl^(-)and H_(2) PO_(4)^(-)were further investigated.As a result,HCO_(3)-and NO_(3)-suppressed the reaction while Cl-and H_(2) PO4-had a double effect on reaction.展开更多
Peroxymonosulfate(PMS)activation and photocatalysis are effective technologies to remove organic pollutants,but the adsorption effect of the catalyst is usually unheeded in degradation process.Herein,a bifunctional ca...Peroxymonosulfate(PMS)activation and photocatalysis are effective technologies to remove organic pollutants,but the adsorption effect of the catalyst is usually unheeded in degradation process.Herein,a bifunctional catalyst of amorphous MoS_(x)(a-MoS_(x))with 3D layer-by-layer superstructure was synthesized by assembling basic active units[Mo_(3)S_(13)]^(2-)of MoS_(2).The large interlayer spacing and high exposure of active sites render a-MoS_(x)to have excellent synergy of adsorption and photo-assisted PMS activation for tetracycline(TC)degradation.Experiments and DFT calculation show that TC can be efficiently enriched on a-MoS_(x)by pore filling,π-πinteraction,hydrogen bonding and high adsorption energy.Subsequently,PMS can be quickly activated through electron transfer with a-MoS_(x),resulting in high TC degradation efficiency of 96.6%within 20 min.In addition,the synergistic mechanism of adsorption and photo-assisted PMS activation was explored,and the degradation pathway of TC was expounded.This work is inspirational for constructing bifunctional catalysts with superior synergistic adsorption and catalytic capabilities to remove refractory organic pollutants in water.展开更多
The nitrogen-doped carbon derived from graphitic carbon nitride(g-C_(3)N_(4))has been widely deployed in activating peroxymonosulfate(PMS)to remove organic pollutants.However,the instability of g-C_(3)N_(4)at high tem...The nitrogen-doped carbon derived from graphitic carbon nitride(g-C_(3)N_(4))has been widely deployed in activating peroxymonosulfate(PMS)to remove organic pollutants.However,the instability of g-C_(3)N_(4)at high temperature brings challenges to the preparation of materials.The nitrogen-doped graphitic carbon nanosheets(N-GC750)were synthesized by magnesium thermal denitrification.Magnesium undergoes the displacement reaction with small molecules produced by the pyrolysis of g-C_(3)N_(4),thereby effectively fixing carbon on the in-situ template of Mg_(3)N_(2)and avoiding direct product volatilization.N-GC750 exhibited excellent performance during the PMS activation process and bisphenol A(BPA,0.2 g/L)could be thoroughly removed in 30 min.A wide range of pH(3–11),temperature(10–40℃)and common anions were employed in studying the impact on system.Additionally,N-GC750 showed satisfactory reusability in cycle tests and promising applicability in real water samples.Quenching experiments and electron paramagnetic resonance(EPR)measurements indicated that singlet oxygen was the main active species coupled with partial electron transfer in N-GC750/PMS system.Furtherly,the oxidation products were identified,and their ecotoxicity was evaluated.This work is expected to provide a reference for the feasibility of preparing g-C_(3)N_(4)derived carbon materials and meaningful for PMS activation.展开更多
Formaldehyde(FA),as an important chemical raw material,has been widely used in many fields.However,the discharge of a large amount of FA-containing wastewater poses a serious threat to the environment and human health...Formaldehyde(FA),as an important chemical raw material,has been widely used in many fields.However,the discharge of a large amount of FA-containing wastewater poses a serious threat to the environment and human health.Recently,the in-situ hydrogen energy release technology of hydrogen-containing stable liquid has been extensively explored due to its safe storage.Exploring a robust method to achieve FA removal and synchronous in-situ hydrogen release from FA containing wastewater is of great significant for environmental protection and energy crisis alleviation.Here,we have innovatively introduced peroxymonosulfate(PMS)activation technology into FA removal and hydrogen production simultaneously.The composite of nitrogen doped carbon coating Co_(9)S_(8)nanotubes(Co_(9)S_(8)@N-C)is employed as a proof of concept for FA decomposition and simultaneously hydrogen production based on PMS activation system.As expected,the Co_(9)S_(8)@N-C/PMS system presents much superior hydrogen production efficiency and satisfactory FA removal rate towards FA wastewater than those of common catalysis,photocatalysis and Fenton reaction in the basic condition in a wide range of FA concentration.The hydrogen yield reaches a value as high as 471μmol within 60 min,corresponding to a FA degradation rate of 30%with an initial FA concentration of 0.722 mol L^(-1).Characterizations and density functional theory(DFT)calculations suggest that the free radical process dominated by superoxide radical(O_(2)·^(-))and nonradical process dominated by singlet oxygen(^(1)O_(2)),which are induced by Co_(9)S_(8)@N-C/PMS system,are responsible for highly efficient hydrogen production via FA degradation.These generated O_(2)·^(-)and ^(1)O_(2)can extract·H from FA to form·OOH intermediate,which can further combine with the·H from water to produce hydrogen.This study provides an applicable technique for environmental purification and new energy development based on FA containing wastewater.展开更多
文摘Peroxymonosulfate(PMS)-assisted visible-light photocatalytic degradation of organic pollutants using graphitic carbon nitride(g-C_(3)N_(4))presents a promising and environmentally friendly approach.However,pristine g-C_(3)N_(4) suffers from limited visible-light absorption and low charge-carrier mobility.In this study,a phosphorus-doped tubular carbon nitride(5P-TCN)was synthesized via a precursor self-assembly method using phosphoric acid and melamine as raw materials,eliminating the need for organic solvents or templates.The 5P-TCN catalyst demonstrated enhanced visible-light absorption,improved charge transfer capability,and a 5.25-fold increase in specific surface area(31.092 m^(2)/g),which provided abundant active sites to efficiently drive the PMS-assisted photocatalytic reaction.The 5P-TCN/vis/PMS system exhibited exceptional degradation performance for organic pollutants across a broad pH range(3–9),achieving over 92%degradation of Rhodamine B(RhB)within 15 min.Notably,the system retained>98%RhB degradation efficiency after three consecutive operational cycles,demonstrating robust operational stability and reusability.Moreover,key parameters influencing,active radi-cals,degradation pathways,and potential mechanisms for RhB degradation were systematically investigated.This work proposes a green and cost-effective strategy for developing high-efficiency photocatalysts,while demon-strating the exceptional capability of a PMS-assisted photocatalytic system for rapid degradation of RhB.
基金supported by the National Natural Science Foundation of China(No.42376204)the Shandong Provin-cial Natural Science Foundation(No.ZR2022MD023)+3 种基金the Interna-tional Partnership Program by Chinese Academy of Sciences(No.058GJHZ2023058FN)the Young Elite Scientists Sponsorship Pro-gram by CAST(No.YESS20210201)the Key R&D Program of Shan-dong Province,China(Nos.2022CXPT027 and 2023CXPT008)Guangxi Science and Technology Program(Guike AA23026007).
文摘Cobalt-based catalysts were regarded as highly effective for pollutant degradation through peroxymono-sulfate activation.Nevertheless,conventional synthesis methods for cobalt-based catalysts were associ-ated with issues of cobalt ion leakage,which posed a risk of secondary environmental contamination.Addressing this issue,a novel cobalt-based catalyst,CoS nanoparticles,was biosynthesized by Shewanella algae and designated as SA@CoS.SA@CoS,a nanoflower coated with proteins/peptides,contained a sig-nificant number of sulfur vacancies.Compared to chemically synthesized CoS,SA@CoS exhibited lower cobalt ion release(0.13 mg/L)and higher catalytic activity.Based on this,SA@CoS was employed to de-grade Rhodamine B(RhB)and tetracycline(TC)by activating peroxymonosulfate.The results indicated that the degradation efficiencies of RhB and TC could reach 99.9%and 90.5%within 10 min,respec-tively.Further analyses revealed that both radical(·O_(2)^(-),·OH and SO_(4)^(·-))and non-radical(_(1)O_(2))pathways were involved in the degradation of RhB and TC,with the non-radical pathway dominating the degra-dation process.This work not only offered a facile approach for the biosynthesis of stable cobalt-based catalysts,but also underscored the immense potential of biogenic nano-catalysts in the realm of environ-mental remediation.
文摘The regulation of peroxymonosulfate(PMS)activation by constructing oxygen vacancy and heterogeneous interface catalytic is crucial towards the oxidation of refractory pollutants still remains a major hurdle.This work demonstrates a strategy to constructed ethylene glycol(EG)well-coupled S-scheme heterojunction of NiFe_(2)O_(4-x)/NiS with oxygen vacancy(VO)-modified to efficiently achieve pollutant removal by activating PMS through photoexcitation,a 99%PMS decomposition efficiency is achieved.Photoassisted Kelvin probe force microscopy and in-situ electron spin resonance verify the establishment of a charge-transfer pathway consistent in NiFe_(2)O_(4-x)/NiS with an S-scheme heterojunction,which dramatically provides abundant active sites and distinct charge transport pathway for organic pollutant oxidation.The S-scheme NiFe_(2)O_(4-x)/NiS heterojunction in the photo-Fenton-like system exhibited significantly enhanced degradation rate(0.15 min^(-1))at a low PMS dosage of 0.1 g/L,which is 19 times greater than that of the pristine NiS(0.0077 min^(-1)).Density functional theory calculations confirmed that VO in NiFe_(2)O_(4-x)/NiS efficiently promoted PMS adsorption and lowered the energy barrier for electron transfer.Moreover,in-situ experiments and experimental evidence offer mechanistic insights into the PMS activation through photoexcitation,unraveling a dual-pathway activation mechanism involving reduction and oxidation processes over NiFe_(2)O_(4-x)/NiS during the reaction.This work emphasizes the potential of vacancy engineering synergistic S-scheme heterojunction in developing efficient catalysts for regulating PMS activation,providing a promising solution the cost-effective and efficient treatment of organic wastewater.
文摘The influence of electronic structure on the performance of catalysts for peroxymonosulfate(PMS)activation remains ambiguous.In this study,the 3d electron configuration of Fe(Ⅲ)in AgFeO_(2) was atomically regulated using cobalt doping.The amount of PMS adsorbed and the catalytic performance were positively correlated with the total effective magnetic moment and the ratios of high-spin Fe(Ⅲ)and eg filling within the catalysts.These 3d electron regulations favor PMS adsorption and electron transfer owing to the lower PMS adsorption energy,increased electronic states near the Fermi level,and reduced dz^(2) orbital occupancy.Benefiting from fine tailoring of the electron configuration,the AgFe_(0.80)Co_(0.20)O_(2) catalyst exhibited outstanding catalytic PMS activation and favorable application potential,achieving efficient pharmaceutical wastewater treatment and more than 80%ofloxacin removal after 72 h of continuous-flow operation.Notably,this study offers a comprehensive understanding for the influence mechanism of electronic structure regulation on PMS activation,providing design guidance for the development of efficient heterogeneous Fenton-like catalytic systems.
基金supported by the National Natural Science Foundation of China(Nos.22406081,22276086,22306086)the Natural Science Foundation of Jiangxi Province(No.20232BAB213029),all of which are greatly acknowledged by the authors.
文摘Fenton-like technology based on peroxymonosulfate activation has shown great potential in refractory organics degradation.In this work,single Fe atom catalysts were synthesized through facile ball milling and exhibited very high performance in peroxymonosulfate activation.The Fe single-atom filled an N vacancy on the triazine ring edge of C_(3)N_(4),as confirmed through X-ray absorption fine structure,density functional calculation and elec-tron paramagnetic resonance.The SAFe_(0.4)–C_(3)N_(4)/PMS system could completely remove phenol(20 mg/L)within 10 min and its first-order kinetic constant was 12.3 times that of the Fe_(3)O_(4)/PMS system.Under different ini-tial pH levels and in various anionic environments,SAFe_(0.4)–C_(3)N_(4) still demonstrated excellent catalytic activity,achieving a removal rate of over 90%for phenol within 12 min.In addition,SAFe_(0.4)–C_(3)N_(4) exhibited outstanding selectivity in reaction systems with different pollutants,showing excellent degradation effects on electron-rich pollutants only.Hydroxyl radicals(•OH),singlet oxygen(1O_(2))and high-valent iron oxide(Fe(Ⅳ)=O)were de-tected in the SAFe_(0.4)–C_(3)N_(4)/PMS system through free radical capture experiments.Further experiments on the quenching of active species and a methyl phenyl sulfoxide probe confirmed that 1O_(2) and Fe(Ⅳ)=O played dom-inant roles.Additionally,the change in the current response after adding PMS and phenol in succession proved that a direct electron transfer path between organic matter and the catalyst surface was unlikely to exist in the SAFe_(0.4)–C_(3)N_(4)/PMS/Phenol degradation system.This study provides a new demonstration of the catalytic mech-anism of single-atom catalysts.
基金This work was supported by the National Natural Science Foundation of China(Nos.51978178 and 51521006)the Department of Science and Technology of Guangdong Province of China(Nos.2019A1515012044 and 2021A1515011797)+3 种基金the International S&T Cooperation Program of China(No.2015DFG92750)the Maoming Municipal Bureau of Science and Technology of Guangdong of China(No.2018S0013)the Startup Fund of Guangdong University of Petrochemical Technology(No.2020rc041)the Shanghai Tongji Gao Tingyao Environmental Science&Technology Development Foundation.
文摘Nonradical reaction driven by peroxymonosulfate(PMS)based advanced oxidation pro-cesses has drawn widespread attention in water treatment due to their inherent advantages,but the degradation behavior and mechanism of organic pollutants are still unclear.In this study,the performance,intermediates,mechanism and toxicity of tetracycline(TC)degra-dation were thoroughly examined in the constructed magnetic nitrogen-doped porous car-bon/peroxymonosulfate(Co-N/C-PMS)system.The results showed that 85.4%of TC could be removed within 15 min when Co-N/C and PMS was simultaneously added and the degra-dation rate was enhanced by 3.4 and 14.7 folds compared with Co-N/C or PMS alone,re-spectively.Moreover,the performance of Co-N/C was superior to that of most previously reported catalysts.Many lines of evidence indicated that Co-N/C-PMS system was a singlet oxygen-dominated nonradical reaction,which was less interfered by pH and water compo-nents,and displayed high adaptability to actual water bodies.Subsequently,the degrada-tion process was elaborated on the basis of three-dimensional excitation-emission matrix spectra and liquid chromatography-mass spectrometry.At last,the toxicity of treated TC was greatly reduced by using microalgae Coelastrella sp.as ecological indicator.This study provides a promising approach based on singlet oxygen-dominated nonradical reaction for eliminating TC in water treatment.
基金supported by the Natural Science Foundation of Jiangsu Province(BK20160936,BK20160938)the National Natural Science Foundation of China(51708297)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)~~
文摘Excitation of metal-free graphitic carbon nitride(g-C3N4) under visible light can successfully achieve efficient activation of peroxymonosulfate(PMS). Synergistic effects and involved mechanism were systematically investigated using a light-inert endocrine disrupting compound, dimethyl phthalate(DMP), as the target pollutant. Under visible light irradiation, DMP could not be degraded by direct g-C3 N4-mediated photocatalysis, while in the presence of PMS, the dominant radicals were converted from ·O2 to SO4·– and ·OH, resulting in effective DMP degradation and mineralization. Results showed that higher dosage of PMS or g-C3 N4 could increase the activation amount of PMS and corresponding DMP degradation efficiency, but the latter approach was more productive in terms of making the most of PMS. High DMP concentration hindered effective contact between PMS and g-C3 N4, but could provide efficient use of PMS. Higher DMP degradation efficiency was achieved at p H lower than the point of zero charge(5.4). Based on intermediates identification, the DMP degradation was found mainly through radical attack(·OH and SO4·–) of the benzene ring and oxidation of the aliphatic chains.
基金financially supported by the National Natural Science Foundation of China(Nos.52070046,52122009,51808140and 51838005)the Introduced of Innovative R&D Team Project under the“Pearl River Talent Recruitment Program”of Guangdong Province(No.2019ZT08L387)+1 种基金the Guangdong Province Universities and Colleges Pearl River Scholar Funded Scheme(Young Scholar)the support from the BL14W1beamline of Shanghai Synchrotron Radiation Facility(SSRF,China)。
文摘Peroxymonosulfate(PMS)activation in heterogeneous processes is a promising water treatment technology.Nevertheless,the high energy consumption and low efficiency during the reaction are ineluctable,due to electron cycling rate limitation.Herein,a new strategy is proposed based on a quantum dots(QDs)/PMS system.Co-ZnS QDs are synthesized by a water phase coprecipitation method.The inequivalent lattice-doping of Co for Zn leads to the generation of surface sulfur vacancies(SVs),which modulates the surface of the catalyst to form an electronic nonequilibrium surface.Astonishingly,the plasticizer micropollutants can be completely degraded within only tens of seconds in the Co-Zn S QDs/PMS system due to this type of surface modulation.The interfacial reaction mechanism is revealed that pollutants tend to be adsorbed on the cobalt metal sites as the electron donors,where the internal electrons of pollutants are captured by the metal species and transferred to the surface SVs.Meanwhile,PMS adsorbed on the SVs is reduced to radicals by capturing electrons,achieving effective electron recovery.Dissolved oxygen(DO)molecules are also easily attracted to catalyst defects and are reduced to O_(2)^(·-),further promoting the degradation of pollutants.
基金supported by the National Key Research and Development Program of China (2016YFB0700504)~~
文摘An environmentally friendly Mn‐oxide‐supported metal‐organic framework(MOF),Mn3O4/ZIF‐8,was successfully prepared using a facile solvothermal method,with a formation mechanism proposed.The composite was characterized using X‐ray diffraction,scanning electron microscopy,transmission electron microscopy,X‐ray photoelectron microscopy,and Fourier‐transform infrared spectroscopy.After characterization,the MOF was used to activate peroxymonosulfate(PMS)for degradation of the refractory pollutant rhodamine B(RhB)in water.The composite prepared at a0.5:1mass ratio of Mn3O4to ZIF‐8possessed the highest catalytic activity with negligible Mn leaching.The maximum RhB degradation of approximately98%was achieved at0.4g/L0.5‐Mn/ZIF‐120,0.3g/L PMS,and10mg/L initial RhB concentration at a reaction temperature of23°C.The RhB degradation followed first‐order kinetics and was accelerated with increased0.5‐Mn/ZIF‐120and PMS dosages,decreased initial RhB concentration,and increased reaction temperature.Moreover,quenching tests indicated that?OH was the predominant radical involved in the RhB degradation;the?OH mainly originated from SO4??and,hence,PMS.Mn3O4/ZIF‐8also displayed good reusability for RhB degradation in the presence of PMS over five runs,with a RhB degradation efficiency of more than96%and Mn leaching of less than5%for each run.Based on these findings,a RhB degradation mechanism was proposed.
基金supported by the National Natural Science Foundation of China(Nos.51878431,51878465)the Fundamental Research Funds for the Central Universities(Nos.22120180504)
文摘The widely used carbamazepine(CBZ)is one of the most persistent pharmaceuticals and suffers insufficient removal efficiency by conventional wastewater treatment.A synthesized Co-based perovskite(LaCoO3)was used to activate peroxymonosulfate(PMS)in order to degrade CBZ.Results showed that LaCoO3 exhibited an excellent performance in PMS activation and CBZ degradation at neutral pH,with low cobalt leaching.The results of FT-IR and XPS verified the high structurally and chemically stability of LaCoO3 in PMS activation.Electron spin resonance(ESR)analysis suggested the generation of radical species,such as sulfate radicals(SO4·-)and hydroxyl radicals(·OH).Radical quenching experiments further revealed the responsibility of SO4·-as the dominant oxidant for CBZ oxidation.Ten products were detected via the oxidation of CBZ,with the olefinic double bond attacked by SO4·-as the initial step.Hydroxylation,hydrolysis,cyclization and dehydration were involved along the transformation of CBZ.The toxicity of CBZ solution was significantly reduced after treating by PMS/LaCoO3.
基金the National Natural Science Foundation of China(No.51978319)National College Student Innovation and Entrepreneurship Training Program of Lanzhou UniversityKey Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources,Qinghai Institute of Salt Lake,Chinese Academy of Sciences。
文摘In this study,Fe_(2)O_(3)/Mn_(2)O_(3) composite was synthesized by a facile two-step technique,and several methods were carried out to characterize it.Then,the decomposition experiments of tartrazine(TTZ),a kind of refractory o rganic pollutant,were conducted under various enviro nmental condition to detect the catalyst performance,such as reaction system,the dosage of catalyst,peroxymonosulfate(PMS)concentration,initial pH,different natural water substances.The results exhibited that Fe_(2)O_(3)/Mn_(2)O_(3) composite with the mole rate 2:3 had the best PMS activation performance and the removal efficiency was 97.3%within 30 min.Besides,the optimum degradation conditions of TTZ we re also discussed,that is catalyst dosage(0.6 g/L),PMS concentration(0.8 g/L)and the initial pH 11.In addition,proved by the natural water substances adding experiments,HPO_(4)^(2)-,HCO_(3)^-,NO_(3)^-and NOM(nature organic matter)could slow down the experiments progressing,but Cl^-could boost it.Then inhibitor experiments indicated both the HO^·and SO_(4)^·-played a vital role in the experiments.Reusability and ions leaching experiments as well as the used catalyst physical characte rization images exhibited the excellent stability and cyclicity of the Fe_(2)O_(3)/Mn_(2)O_(3) composite.Finally,based on the XPS(X-ray photoelectro n spectro scopy)and the experiments results,the possible mechanism of TTZ degradation was proposed.This system might provide a novel thought for the decomposition of refractory organic pollutant and had potential in promotion of actual sewage treatment technology.
基金supported by the National Key Research and Development Program of China (Project No.2018YFB1502903)。
文摘Metal-based perovskite oxides have contributed significantly to the advanced oxidation processes(AOPs)due to their diverse active sites and excellent compositional/structural flexibility.In this study,we specially designed a perovskite oxide with abundant oxygen vacancies,SrCo_(0.8)Fe_(0.2)O_(3)(SCF),and firstly applied it as a catalyst in peroxymonosulfate(PMS) activation towards organic pollutants degradation.The result revealed that the prepared SCF catalyst exhibited excellent performance on organic compounds degradation.Besides,SCF showed much better activity than La_(0.5)Sr_(0.5)Co_(0.8)Fe_(0.2)O_(3)(LSCF) in terms of reaction rate and stability for the degradation of the organic compounds.Based on the analysis of scanning electron microscope,transmission electron microscope,X-ray diffraction,N_(2) adsorption-desorption,X-ray photoelectron spectroscopy and electron paramagnetic resonance,it was confirmed that the perovskite catalysts with high content of Sr doping at A-site could effectively create a defect-rich surface and optimize its physicochemical properties,which was responsible for the excellent heterogeneous catalytic activity of SCF.SCF can generate three highly active species:~1 O_(2),SO_(4)^(-)· and ·OH in PMS activation,revealing the degradation process of organic compounds was a coupled multiple active species in both radical and nonradical pathway.Moreover,it was mainly in a radical pathway in the degradation through PMS activation on SCF and SO_(4)^(-)· radicals produced were the dominant species in SCF/PMS system.This study demonstrated that perovskite-type catalysts could enrich OVs efficiently by doping strategy and regulate the PMS activation towards sulfate radical-based AOPs.
基金partially supported by the National Natural Science Foundation of China(Nos.21906001 and 51721006)supported by MOE Key Laboratory of Resources and Environmental Systems Optimization(NCEPU)
文摘Hollow microsphere structure cobalt hydroxide(h-Co(OH)2) was synthesized via an optimized solvothermal-hydrothermal process and applied to activate peroxymonosulfate(PMS) for degradation of a typical pharmaceutically active compound,ibuprofen(IBP).The material characterizations confirmed the presence of the microscale hollow spheres with thin nanosheets shell in h-Co(OH)2,and the crystalline phase was assigned to a-Co(OH)2.h-Co(OH)2 could efficiently activate PMS for radicals production,and 98.6% of IBP was degraded at 10 min.The activation of PMS by h-Co(OH)2 was a pHindependent process,and pH 7 was the optimum condition for the activation-degradation system.Scavenger quenching test indicated that the sulfate radical(SO4^·-) was the primary reactive oxygen species for IBP degradation,which contributed to 75.7%.Fukui index(f^-) based on density functional theory(DFT) calculation predicted the active sites of IBP molecule for SO4^·- attack,and then IBP degradation pathway was proposed by means of intermediates identification and theoretical calculation.The developed hollow Co(OH)2 used to efficiently activate PMS is promising and innovative alternative for organic contaminants removal from water and wastewater.
基金financially supported by the National Natural Science Foundation of China(Nos.52170079 and U20A20322)the Programme of Introducing Talents of Discipline to Universities,China(No.B16020)。
文摘The Z-scheme heterostructure for photocatalyst can effectively prolong the lifetime of photogenerated carriers and retain a higher conduction/valence band position,promoting the synergistic coupling of photocatalysis and peroxymonosulfate(PMS) activation.In order to fully utilize the luminous energy and realize the efficient activation of PMS,this work achieved successful construction of NiCo_(2)O_(4)/BiOCl/Bi_(24)O_(31)Br_(10) ternary Z-scheme heterojunction by simultaneously synthesizing BiOCl and NiCo_(2)O_(4) with NiCl_(2) and CoCl_(2) as the precursors.The intercalated BiOCl could serve as a carrier migration ladder to further achieve the spatial separation of electron-hole pairs,so that the oxidation and reduction processes separately occurred in different regions.Compared with the reported catalysts,the as-prepared composites exhibited the enhanced removal efficiency for tetracycline hydrochloride(TCH) in the visible light/PMS system,with a degradation efficiency of 85.30%in 2 min,and possessed good stability.Z-scheme heterojunction was shown to be beneficial for maximizing the superiority of photo-assisted Fenton-like reaction system.The experimental and characterization results confirmed that both non-radicals(^(1)O_(2)) and radicals(SO_(5)^(·-) and SO_(4)^(·-)) were involved in the reaction process and the SO_(5)^(·-)generated by the oxidation of PMS played a crucial role in the TCH degradation.The possible reaction mechanism was finally proposed.This study provided new insight into the Z-scheme heterostructure to promote the photo-assisted Fenton-like reaction.
基金founding support from the National Natural Science Foundation of China(Nos.21906072,22006057 and 31971616)the Natural Science Foundation of Jiangsu Province(BK20190982)+4 种基金“Doctor of Mass Entrepreneurship and Innovation”Project in Jiangsu Province,Henan Postdoctoral Foundation(202003013)Doctoral Scientific Research Foundation of Jiangsu University of Science and Technology(China)(1062931806 and 1142931803)the Science and Technology Research Project of the Department of Education of Jilin Province(JJKH20200039KJ)the Science and Technology Research Project of Jilin City(20190104120,201830811)the Project of Jilin Provincial Science and Technology Development Plan(20190201277JC,20200301046RQ,YDZJ202101ZYTS070)。
文摘β-lactam antibiotics in aquatic environment have severely damaged ecological stability and caused a series of environmental pollution problems to be solved urgently.Herein,a novel composite photocatalyst prepared by loading carbon dots(CDs)onto rod-like CoFe_(2)O_(4)(CFO),which can effectively degrade amoxicillin(AMX)by photocata lytic/peroxy mono sulfate(PMS)activation under visible light irradiation.The degradation results exhibits that the optimal degradation efficiency with 97.5%within 80 min is achievd by the CDs-CFO-5 composite.Such enhanced activity is ascribed to the introduction of CDs that effectively improves the separation efficiency of photogenerated electron pairs and creates new active sites as electron bridges that improve the photocata lytic performance.More importantly,a strong synergistic between CDs and photo-induced electrons generated from CFO can further activiate PMS to provide more SO4-·and·OH radicals for boosting the degradation ability towards AMX.The present study aims to elucidate positive role of CDs in photocata lytic/peroxy monosulfate activation during the degradation reaction.
基金supported by the Hebei Natural Science Foundation (No.B2020208064)the Double Tops Joint Fund of the Yunnan Science and Technology Bureau and Yunnan University (No.2019FY003025)Shijiazhuang Science and Technology Department (No.191240263A)。
文摘Morphology and dispersity are key factors for activating peroxymonosulfate(PMS).In this study,we designed a recyclable open-type NiCo_(2)O_(4) hollow microsphere via a simple hydrothermal method with the assistance of an NH_(3) vesicle.The physical structure and chemical properties were characterized using techniques such as scanning electron microscope(SEM),transmission electron microscope(TEM),X-ray diffraction(XRD),N2 adsorption and X-ray photoelectron spectroscopy(XPS).The test results confirm that the inner and outer surfaces of open-type NiCo_(2)O_(4) hollow-sphere can be efficiently utilized because of the hole on the surface of the catalyst,which can minimize the diffusion resistance of the reactants and products.Under optimized conditions,the total orga nic carbon(TOC) removal efficiency of rhodamine B(RhB) can reach up to 80% in 40 min,which is almost 50% shorter than the reported values.The reactive radicals were identified and the proposed reaction mechanism was well described.Moreover,the disturbances of HCO_(3)^(-),NO_(3)^(-),Cl^(-)and H_(2) PO_(4)^(-)were further investigated.As a result,HCO_(3)-and NO_(3)-suppressed the reaction while Cl-and H_(2) PO4-had a double effect on reaction.
基金supported by the National Natural Science Foundation of China(Nos.52370073,12274115)Program for Science and Technology Innovation Team in Universities of Henan Province(No.24IRTSTHN017)+3 种基金Natural Science Foundation of Henan Province(No.212300410336)Program for Science and Technology Innovation Talent in Universities of Henan Province(No.23HASTIT027)Key Scientific and Technological Project of Henan Province(No.222102320188)Key Project of Science and Technology Research of Henan Provincial Department of Education(No.21A430008)。
文摘Peroxymonosulfate(PMS)activation and photocatalysis are effective technologies to remove organic pollutants,but the adsorption effect of the catalyst is usually unheeded in degradation process.Herein,a bifunctional catalyst of amorphous MoS_(x)(a-MoS_(x))with 3D layer-by-layer superstructure was synthesized by assembling basic active units[Mo_(3)S_(13)]^(2-)of MoS_(2).The large interlayer spacing and high exposure of active sites render a-MoS_(x)to have excellent synergy of adsorption and photo-assisted PMS activation for tetracycline(TC)degradation.Experiments and DFT calculation show that TC can be efficiently enriched on a-MoS_(x)by pore filling,π-πinteraction,hydrogen bonding and high adsorption energy.Subsequently,PMS can be quickly activated through electron transfer with a-MoS_(x),resulting in high TC degradation efficiency of 96.6%within 20 min.In addition,the synergistic mechanism of adsorption and photo-assisted PMS activation was explored,and the degradation pathway of TC was expounded.This work is inspirational for constructing bifunctional catalysts with superior synergistic adsorption and catalytic capabilities to remove refractory organic pollutants in water.
基金the Science and Technology Commission of Shanghai Municipality(Nos.21ZR1425200,18020500800,18JC1412900 and 19DZ2271100)。
文摘The nitrogen-doped carbon derived from graphitic carbon nitride(g-C_(3)N_(4))has been widely deployed in activating peroxymonosulfate(PMS)to remove organic pollutants.However,the instability of g-C_(3)N_(4)at high temperature brings challenges to the preparation of materials.The nitrogen-doped graphitic carbon nanosheets(N-GC750)were synthesized by magnesium thermal denitrification.Magnesium undergoes the displacement reaction with small molecules produced by the pyrolysis of g-C_(3)N_(4),thereby effectively fixing carbon on the in-situ template of Mg_(3)N_(2)and avoiding direct product volatilization.N-GC750 exhibited excellent performance during the PMS activation process and bisphenol A(BPA,0.2 g/L)could be thoroughly removed in 30 min.A wide range of pH(3–11),temperature(10–40℃)and common anions were employed in studying the impact on system.Additionally,N-GC750 showed satisfactory reusability in cycle tests and promising applicability in real water samples.Quenching experiments and electron paramagnetic resonance(EPR)measurements indicated that singlet oxygen was the main active species coupled with partial electron transfer in N-GC750/PMS system.Furtherly,the oxidation products were identified,and their ecotoxicity was evaluated.This work is expected to provide a reference for the feasibility of preparing g-C_(3)N_(4)derived carbon materials and meaningful for PMS activation.
基金the National Natural Science Foundation of China(Nos.21975193 and 51602237)the Fundamental Research Funds for the Central Universities,China(WUT:2021Ⅲ034JC)。
文摘Formaldehyde(FA),as an important chemical raw material,has been widely used in many fields.However,the discharge of a large amount of FA-containing wastewater poses a serious threat to the environment and human health.Recently,the in-situ hydrogen energy release technology of hydrogen-containing stable liquid has been extensively explored due to its safe storage.Exploring a robust method to achieve FA removal and synchronous in-situ hydrogen release from FA containing wastewater is of great significant for environmental protection and energy crisis alleviation.Here,we have innovatively introduced peroxymonosulfate(PMS)activation technology into FA removal and hydrogen production simultaneously.The composite of nitrogen doped carbon coating Co_(9)S_(8)nanotubes(Co_(9)S_(8)@N-C)is employed as a proof of concept for FA decomposition and simultaneously hydrogen production based on PMS activation system.As expected,the Co_(9)S_(8)@N-C/PMS system presents much superior hydrogen production efficiency and satisfactory FA removal rate towards FA wastewater than those of common catalysis,photocatalysis and Fenton reaction in the basic condition in a wide range of FA concentration.The hydrogen yield reaches a value as high as 471μmol within 60 min,corresponding to a FA degradation rate of 30%with an initial FA concentration of 0.722 mol L^(-1).Characterizations and density functional theory(DFT)calculations suggest that the free radical process dominated by superoxide radical(O_(2)·^(-))and nonradical process dominated by singlet oxygen(^(1)O_(2)),which are induced by Co_(9)S_(8)@N-C/PMS system,are responsible for highly efficient hydrogen production via FA degradation.These generated O_(2)·^(-)and ^(1)O_(2)can extract·H from FA to form·OOH intermediate,which can further combine with the·H from water to produce hydrogen.This study provides an applicable technique for environmental purification and new energy development based on FA containing wastewater.
