Dissolved copper and iron ions are regarded as friendly and economic catalysts for peroxymonosulfate(PMS)activation,however,neither Cu(Ⅱ)nor Fe(Ⅲ)shows efficient catalytic performance because of the slow rates of Cu...Dissolved copper and iron ions are regarded as friendly and economic catalysts for peroxymonosulfate(PMS)activation,however,neither Cu(Ⅱ)nor Fe(Ⅲ)shows efficient catalytic performance because of the slow rates of Cu(Ⅱ)/Cu(Ⅰ)and Fe(Ⅲ)/Fe(Ⅱ)cycles.Innovatively,we observed a significant enhancement on the degradation of organic contaminants when Cu(Ⅱ)and Fe(Ⅲ)were coupled to activate PMS in borate(BA)buffer.The degradation efficiency of Rhodamine B(RhB,20μmol/L)reached up to 96.3%within 10 min,which was higher than the sum of individual Cu(Ⅱ)-and Fe(Ⅲ)-activated PMS process.Sulfate radical,hydroxyl radical and high-valent metal ions(i.e.,Cu(Ⅲ)and Fe(IV))were identified as the working reactive species for RhB removal in Cu(Ⅱ)/Fe(Ⅲ)/PMS/BA system,while the last played a predominated role.The presence of BA dramatically facilitated the reduction of Cu(Ⅱ)to Cu(Ⅰ)via chelating with Cu(Ⅱ)followed by Fe(Ⅲ)reduction by Cu(Ⅰ),resulting in enhanced PMS activation by Cu(Ⅰ)and Fe(Ⅱ)as well as accelerated generation of reactive species.Additionally,the strong buffering capacity of BA to stabilize the solution pH was satisfying for the pollutants degradation since a slightly alkaline environment favored the PMS activation by coupling Cu(Ⅱ)and Fe(Ⅲ).In a word,this work provides a brand-new insight into the outstanding PMS activation by homogeneous bimetals and an expanded application of iron-based advanced oxidation processes in alkaline conditions.展开更多
Owing to outstanding hydrophilicity and ionic interaction,layered double hydroxides(LDHs)have emerged as a promising carrier for high performance catalysts.However,the synthesis of new specialized catalytic LDHs for d...Owing to outstanding hydrophilicity and ionic interaction,layered double hydroxides(LDHs)have emerged as a promising carrier for high performance catalysts.However,the synthesis of new specialized catalytic LDHs for degradation of antibiotics still faces some challenges.In this study,a CoFe_(2)O_(4)/MgAl-LDH composite catalyst was synthesized using a hydrothermal coprecipitation method.Comprehensive characterization reveals that the surface of MgAl-LDH is covered with nanometer CoFe_(2)O_(4) particles.The specific surface area of CoFe_(2)O_(4)/MgAl-LDH is 82.84 m^(2)·g^(-)1,which is 2.34 times that of CoFe_(2)O_(4).CoFe_(2)O_(4)/MgAl-LDH has a saturation magnetic strength of 22.24 A·m^(2)·kg^(-1) facilitating efficient solid-liquid separation.The composite catalyst was employed to activate peroxymonosulfate(PMS)for the efficient degradation of tetracycline hydrochloride(TCH).It is found that the catalytic performance of CoFe_(2)O_(4)/MgAl-LDH significantly exceeds that of CoFe_(2)O_(4).The maximum TCH removal reaches 98.2%under the optimal conditions([TCH]=25 mg/L,[PMS]=1.5 mmol/L,CoFe_(2)O_(4)/MgAl-LDH=0.20 g/L,pH 7,and T=25℃).Coexisting ions in the solution,such as SO_(4)^(2-),Cl-,H_(2)PO_(4)^(-),and CO_(3)^(2-),have a negligible effect on catalytic performance.Cyclic tests demonstrate that the catalytic performance of CoFe_(2)O_(4)/MgAl-LDH remains 67.2%after five cycles.Mechanism investigations suggest that O_(2)^(•-)and ^(1)O_(2) produced by CoFe_(2)O_(4)/MgAl-LDH play a critical role in the catalytic degradation.展开更多
Integrating photocatalysis technology with peroxymonosulfate oxidation possesses huge potential for degrading stubborn pollutant.Herein,a porous ultra-thin carbon nitride with C-defect O-doping and advanced n-π^(∗)tr...Integrating photocatalysis technology with peroxymonosulfate oxidation possesses huge potential for degrading stubborn pollutant.Herein,a porous ultra-thin carbon nitride with C-defect O-doping and advanced n-π^(∗)transition was customized by one-pot thermalinduced polymerization of molten urea assisted with paraformaldehyde.Via visible-light coupling peroxymonosulfate activation,the DCN-100 can completely photodegrade 2,4-dichlorophenol,and rate constant is 136.6 and 37.9 times that of CN and DCN-100 without peroxymonosulfate.The light-absorption of DCN-100 surpasses 550 nm,specific surface area rises from 45.03 to 98.58m^(2)/g,and charge behaviors are significantly improved.The effects of paraformaldehyde amount,PMS dosage,pH,2,4-dichlorophenol concentration,different water-body,wavelength and recycling times on photodegradation performance were explored in detail.Via capture experiments,ESR,LC-MS,Fukui-function,TEXT toxicity assessment and DFT theoretical calculation,themain active substances,degradation pathway,intermediate toxicity and enhanced activity mechanism of DCN-100 were clarified.The research provides a cost-effective,high-efficiency and environmental-friendly photocatalysts to activate peroxymonosulfate for water remediating.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
Bisphenol A(BPA)has threatened ecological safety and human health due to its endocrine disrupting effect and widely diffused in the environment.Peroxymonosulfate(PMS)based on oxidation technology exhibits good potenti...Bisphenol A(BPA)has threatened ecological safety and human health due to its endocrine disrupting effect and widely diffused in the environment.Peroxymonosulfate(PMS)based on oxidation technology exhibits good potential for environmental remediation whereas the highly efficient activator needs to be developed.Herein,the Bi OBr(BOB)was synthesized to efficiently activate PMS to remove 95.6%of BPA within 60 min.The observed rate constant of BPA removal in BOB/PMS system is 0.049 min^(-1),which is 60 and 148 times to that of the BOB and PMS processes separately and 129 times to the compared Bi OCl(BOC)/PMS system,respectively.Comparison experiments and analytic methods demonstrate that BOB with a larger content of oxygen vacancies(Ov)can act as the bridge of electron transfer between Bi^(3+)/Bi^(4+)with PMS to enhance the activation ability for PMS,resulting in the production of abundant reactive oxygen species(O_(2)^(·-)and ^(1)O_(2)).Additionally,the breakdown processes of BPA and the toxicity of its byproducts were uncovered,and the potential for actual water treatment was evaluated to confirm the detoxification,efficiency,stability and practical use of the BOB/PMS system for eliminating BPA.This study may widen the application of traditional semiconductors and develop the cost-effective PMS activation methods for environmental remediation.展开更多
N-doped graphite carbon sphere coated cobalt nanoparticle catalyst(Co@C-N-900),prepared by solvothermal-calcination method,is applied to activate peroxymonosulfate(PMS)for bisphenol A(BPA)elimination.The outcomes demo...N-doped graphite carbon sphere coated cobalt nanoparticle catalyst(Co@C-N-900),prepared by solvothermal-calcination method,is applied to activate peroxymonosulfate(PMS)for bisphenol A(BPA)elimination.The outcomes demonstrate that the Co@C-N-900 could effectively activate PMS,thereby causing efficient removal of BPA in water.In addition,the Co@C-N-900/PMS system also has the advantages of low metal leaching,applicability in high salinity environments,good selectivity and stability.Further investigations using electron paramagnetic resonance,chronoamperometry,and quenching experiments demonstrated that the Co@C-N-900/PMS system is a typical non-radical route with singlet oxygen(^(1)O_(2))as the main reactive oxygen species(ROS).Density functional theory calculations(DFT)indicate that N-doping can effectively regulate the charge distribution on the catalyst surface,generating acidic/alkaline sites favorable for PMS adsorption and activation.Furthermore,it also can enhance the interaction and charge transfer capacity between the Co@C-N-900 and PMS.Lastly,LC-QTOF-MS/MS analysis revealed two possible BPA degradation pathways:(1)^(1)O_(2)attacked the isopropyl group in BPA between the two phenyl groups,causingβ-scission to occur.(2)Following the oxidation of the hydroxyl group in the aromatic ring of BPA,^(1)O_(2)could cause furtherβ-scission.The prepared Co@C-N-900 catalyst is a very promising catalyst,which would offer a workable remedy for treating water pollution.展开更多
Developing a low-cost stable and high-performance peroxymonosulfate(PMS)catalyst to degrade refractory organic pollutants is still an urgent problem.Herein,this study reported FeVO_(4)nanorods decorated sepiolite(FeVO...Developing a low-cost stable and high-performance peroxymonosulfate(PMS)catalyst to degrade refractory organic pollutants is still an urgent problem.Herein,this study reported FeVO_(4)nanorods decorated sepiolite(FeVO_(4)/sepiolite)through simple hydrothermal method as an adsorptive-catalyst for PMS activation to degrade tetracycline(TC).Benefiting from the introduction of sepiolite support,FeVO_(4)nanorods could be uniformly immobilized onto fibrous sepiolite surface.As a result,FeVO_(4)/sepiolite composite was endowed with excellent adsorption properties,rich surface hydroxyl groups,more reaction active sites,and the stable redox cycle of Fe^(3+)/Fe^(2+)and V5^(+)/V4^(+).Therefore,higher TC degradation efficiency(91.19%within 40 min)and larger reaction rate constant(0.1649 min^(-1))were obtained in FeVO_(4)/sepiolite/PMS system than in FeVO_(4)/PMS system.Besides,the composite presented good stability and reusability,and the effects of application parameters on TC degradation were investigated in detail.Through quenching experiment and electron paramagentic resonance(EPR)test,it was found that both radical and non-radical species participates in TC degradation,and ^(1)O_(2) were the main active species.The PMS activation mechanism was proposed,and the possible degradation pathway was also analyzed according to the high performance liquid chromatography-mass spectrometry(HPLC-MS)results.Overall,this work provides meaningful insights for designing natural mineral based PMS activators to effectively remediate antibiotic wastewater.展开更多
In this study,supported Pd catalysts were prepared and used as heterogeneous catalysts for the activation of peroxymonosulfate(PMS)which successfully degrade bisphenol F(BPF).Among the supported catalysts(i.e.,Pd/SiO_...In this study,supported Pd catalysts were prepared and used as heterogeneous catalysts for the activation of peroxymonosulfate(PMS)which successfully degrade bisphenol F(BPF).Among the supported catalysts(i.e.,Pd/SiO_(2),Pd/CeO_(2),Pd/TiO_(2)and Pd/Al2O3),Pd/TiO_(2)exhibited the highest catalytic activity due to the high isoelectric point and high Pd0 content.Pd/TiO_(2)prepared by the deposition method leads to high Pd dispersion,which are the key factors for efficient BPF degradation.The influencing factors were investigated during the reaction process and two possible degradation pathways were proposed.Density functional theory(DFT)calculations demonstrate that stronger BPF adsorption and BPF degradation with lower reaction barrier occurs on smaller Pd particles.The catalytic activities are strongly dependent on the structural features of the catalysts.Both experiments and theoretical calculations prove that the reaction is actuated by electron transfer rather than radicals.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
Rational tuning of crystallographic surface and metal doping were effective to enhance the catalytic performance of metal organic frameworks,but limited work has been explored for achieving modulation of crystal facet...Rational tuning of crystallographic surface and metal doping were effective to enhance the catalytic performance of metal organic frameworks,but limited work has been explored for achieving modulation of crystal facets and metal doping in a single system.MIL-68(In)was promising for photocatalytic applications due to its low toxicity and excellent photoresponsivity.However,its catalytic activity was constrained by severe carrier recombination and a lack of active sites.Herein,increased(001)facet ratio and active sites exposure were simultaneously realized by cobalt doping in MIL-68(In)through a one-pot solvothermal strategy.Optimized MIL-68(In/Co)-2.5 exhibited remarkable catalytic performance in comparison with pristine MIL-68(In)and other MIL-68(In/Co).The reaction kinetic constant and degradation efficiency of MIL-68(In/Co)were approximately twice and 17%higher than the pristine MIL-68(In)in 36 min reaction,respectively.Density functional theory calculations revealed that Co dopant could modulate the orientation of MIL-68(In)facets,facilitate the exchange of electrons and reduce the adsorption energy of peroxymonosulfate(PMS).This work provides a novel pathway for improvement of In-based MOFs in PMS/vis system,it also promotes the profound comprehension of the correlation between crystal facet regulation and catalytic activation in the PMS/vis system.展开更多
An efficient catalytic system was developed to remove various organic pollutants by simultaneously using low-level cobalt ions,calcium carbonate micro-particles and peroxymonosulfate(PMS).A simple base-induced precipi...An efficient catalytic system was developed to remove various organic pollutants by simultaneously using low-level cobalt ions,calcium carbonate micro-particles and peroxymonosulfate(PMS).A simple base-induced precipitation was used to successfully loaded Co-centered reactive sites onto the surface of CaCO_(3)microparticles.Under optimal conditions at 25°C,10 mg/L methylene blue(MB)could be completely degraded within 10 min with 480μg/L Co^(2+),0.4 g/L CaCO_(3)microparticles(or 0.4 g/L Co@CaCO_(3))and 0.1 g/L PMS.The MB degradation followed the pseudo first order kinetics with a rate constant of 0.583 min^(−1),being 8.3,11.5 and 53.0 times that by using Co-OH(0.07 min^(−1)),Co^(2+)(0.044 min^(−1))and CaCO_(3)(0.011 min^(−1))as the catalyst,respectively.It was confirmed that there was a synergistic effect in the catalytic activity between Co species and the CaCO_(3)particles but the major contributor was the highly dispersed Co species.When Co^(2+)-containing simulated electroplating wastewater was used as the Co^(2+)source,not only the added MB was also completely degraded within 5 min in this catalytic system,but also the coexisting heavy metal ions were substantially removed.The presently developed method was applied to simultaneously treat organic wastewater and heavy metals wastewater.The present method was also successfully used to efficiently degrade other organic pollutants including bisphenol A,sulfamethoxazole,rhodamine B,tetrabromobisphenol A,ofloxacin and benzoic acid.A catalytic mechanism was proposed for the PMS activation by Co@CaCO_(3).The surface of CaCO_(3)particles favors the adsorption of Co^(2+).More importantly,the surface of CaCO_(3)particles provides plentiful surface-OH and-CO_(3)^(2+),and these surface groups complex with Co^(2+)to producemore catalytically active species such as surface[CoOH]^(−),resulting in rapid Co^(2+)/Co^(3+)cycling and electron transfer.These interactions cause the observed synergistic effect between Co species and CaCO_(3)particles in PMS activation.Due to good cycle stability,strong anti-interference ability and wide universality,the new method will have broad application prospects.展开更多
The contamination of water resources by phenolic compounds(PCs)presents a significant environmental hazard,necessitating the development of novel materials and methodologies for effective mitigation.In this study,a me...The contamination of water resources by phenolic compounds(PCs)presents a significant environmental hazard,necessitating the development of novel materials and methodologies for effective mitigation.In this study,a metallic copper-doped zeolitic imidazolate framework was pyrolyzed and designated as CuNC-20 for the activation of peroxymonosulfate(PMS)to degrade phenol(PE).Cu-NC-20 could effectively address the issue of metal agglomeration while simultaneously diminishing copper dissolution during the activation of PMS reactions.The Cu-NC-20 catalyst exhibited a rapid degradation rate for PE across a broad pH range(3-9)and demonstrated high tolerance towards coexisting ions.According to scavenger experiments and electron paramagnetic resonance analysis,singlet oxygen(^(1)O_(2))and high-valent copperoxo(Cu(Ⅲ))were the predominant reactive oxygen species,indicating that the system was nonradicaldominated during the degradation process.The quantitative structure-activity relationship(QSAR)between the oxidation rate constants of various substituted phenols and Hammett constants was established.It indicated that the Cu-NC-20/PMS system had the optimal oxidation rate constant withσ^(-)correlation and exhibited a typical electrophilic reaction pattern.This study provides a comprehensive understanding of the heterogeneous activation process for the selective removal of phenolic compounds.展开更多
In this work,atomic Co catalysts are anchored on a three-dimensional(3D)interconnected g-C_(3)N_(4)(SACo-CN)through Co-N coordination,which exhibit efficient charge carrier transition and low activation energy barrier...In this work,atomic Co catalysts are anchored on a three-dimensional(3D)interconnected g-C_(3)N_(4)(SACo-CN)through Co-N coordination,which exhibit efficient charge carrier transition and low activation energy barriers for peroxymonosulfate(PMS).The incorporation of Co atoms extends the absorption spectrum and enhances the photoelectron-hole separation efficiency of the SACo-CN samples.The 3D interconnected structure,combined with the synergistic interplay between Co-N coordination and visible light irradiation,results in SACo-CN catalysts demonstrating excellent catalytic activity and stability for PMS activation.This leads to a degradation rate of 98.8%for oxytetracycline(OTC)within 30 min under visible light.The research proposes three potential mineralization pathways with eight intermediates,leading to a significant decrease in the toxicity of the intermediates.This work provides a facile and promising approach for the preparation of metal single atom catalysts with highly efficient PMS activation performance.展开更多
The degradation of organic pollutants in water is a critical environmental challenge.The iron-doped MoS_(2) catalysts have demonstrated potential in activating peroxymonosulfate(PMS)for environmental remediation,but t...The degradation of organic pollutants in water is a critical environmental challenge.The iron-doped MoS_(2) catalysts have demonstrated potential in activating peroxymonosulfate(PMS)for environmental remediation,but they face challenges such as poor conductivity,limited electron transfer efficiency,and a scarcity of active sites.To address these issues,we successfully synthesized a nano-flowers FeS/MoS_(2) composite derived from polyoxometalates(NH_(4))_(3)[Fe(III)Mo_(6)O_(24)H_(6)]⋅6H_(2)O(denoted as FeMo6)as the bimetallic precursors.This synthesis strategy enhances the interaction between FeS and MoS_(2),thereby facilitating electron transfer.Notably,the introduction of sulfur vacancies in FeS/MoS_(2) exposes additional Mo4t active sites,promoting the redox cycle of Fe^(2+)/Fe^(3+) and accelerating the regeneration of Fe^(2+),which in turn enhances PMS activation.Therefore,a catalytic oxidation system of FeS/MoS_(2)/PMS is presented that primarily relies on SO_(4)^(⋅-)and⋅OH,with ^(1)O_(2) as a supplementary oxidant.This system exhibits exceptional degradation efficiency for p-chlorophenol(4-CP),achieving 100% degradation within 10 min over a wide pH range of 2.4–8.4.The robust performance and wide applicability of FeS/MoS_(2) catalyst make it a promising candidate in advanced oxidation processes(AOPs)for environmental remediation.展开更多
Magnetic Cu^0/Fe3O4 submicron composites were prepared using a hydrothermal method and used as heterogeneous catalysts for the activation of peroxymonosulfate(PMS) and the degradation of organic pollutants.The as-pr...Magnetic Cu^0/Fe3O4 submicron composites were prepared using a hydrothermal method and used as heterogeneous catalysts for the activation of peroxymonosulfate(PMS) and the degradation of organic pollutants.The as-prepared magnetic Cu^0/Fe3O4 submicron composites were composed of Cu^0 and Fe3O4 crystals and had an average size of approximately 220 nm.The Cu^0/Fe3O4 composites could efficiently catalyze the activation of PMS to generate singlet oxygen,and thus induced the rapid degradation of rhodamine B,methylene blue,orange Ⅱ,phenol and 4-chlorophenol.The use of0.1 g/L of the Cu^0/Fe3O4 composites induced the complete removal of rhodamine B(20 μmol/L) in15 min,methylene blue(20 μmol/L) in 5 min,orange Ⅱ(20 μmol/L) in 10 min,phenol(0.1mmol/L) in 30 min and 4-chlorophenol(0.1 mmol/L) in 15 min with an initial pH value of 7.0 and a PMS concentration of 0.5 mmol/L.The total organic carbon(TOC) removal higher than 85%for all of these five pollutants was obtained in 30 min when the PMS concentration was 2.5 mmol/L.The rate of degradation was considerably higher than that obtained with Cu^0 or Fe3O4 particles alone.The enhanced catalytic activity of the Cu^0/Fe3O4 composites in the activation of PMS was attributed to the synergistic effect of the Cu^0 and Fe3O4 crystals in the composites.Singlet oxygen was identified as the primary reactive oxygen species responsible for pollutant degradation by electron spin resonance and radical quenching experiments.A possible mechanism for the activation of PMS by Cu^0/Fe3O4 composites is proposed as electron transfer from the organic pollutants to PMS induces the activation of PMS to generate ^1O2,which induces the degradation of the organic pollutants.As a magnetic catalyst,the Cu^0/Fe3O4 composites were easily recovered by magnetic separation,and exhibited excellent stability over five successive degradation cycles.The present study provides a facile and green heterogeneous catalysis method for the oxidative removal of organic pollutants.展开更多
The adsorption of peroxymonosulfate(PMS)is crucial for PMS activation in the heterogeneous advanced oxidation processes.However,the investigation of PMS adsorption on the piezocatalysts still remains insufficient.In t...The adsorption of peroxymonosulfate(PMS)is crucial for PMS activation in the heterogeneous advanced oxidation processes.However,the investigation of PMS adsorption on the piezocatalysts still remains insufficient.In this work,bismuth oxychloride(BiO Cl)nanosheets were prepared as the piezocatalysts for PMS activation under ultrasonic vibration to remove carbamazepine(CBZ)in aqueous solutions.Up to92.5%of CBZ was degraded for 40 min in Bi OCl piezo-activated PMS system with the reaction rate constant of 0.0741 min-1,being 1.63 times that of the sum of BiOCl piezocatalysis,BiOCl-activated PMS,and vibration-activated PMS.PMS adsorption on the surface of BiOCl was specifically studied by comparing the microscopic structure change of the fresh and used Bi OCl.The results suggested that the piezoelectric field of Bi OCl was able to promote the tight adsorption of PMS on the surface,thus facilitating the fast activation of PMS through electrons transfer to produce reactive species(HO·,SO_(4)·-,O_(2)·-,1O_(2)).This work presents an in-depth understanding for the role of piezoelectric effect on the adsorption and activation of PMS.展开更多
Magnetic CuO nanosheet(Mag-CuO), as a cheap, stable, efficient and easily separated peroxymonosulfate(PMS) activator, was prepared by a simple one-step precipitation method for the removal of organic compounds from sa...Magnetic CuO nanosheet(Mag-CuO), as a cheap, stable, efficient and easily separated peroxymonosulfate(PMS) activator, was prepared by a simple one-step precipitation method for the removal of organic compounds from salt-containing wastewater.The experiments showed that the removal efficiencies of various organic pollutants including Acid Orange 7, Methylene Blue, Rhodamine B and atrazine in a high-salinity system(0.2 mol/L Na2SO4) with the Mag-CuO/PMS process were 95.81%, 74.57%, 100% and 100%,respectively.Meanwhile, Mag-CuO still maintained excellent catalytic activity in other salt systems including one or more salt components(NaCl, NaNO3, Na2HPO4, NaHCO3).A radical-quenching study and electron paramagnetic resonance analysis confirmed that singlet oxygen(1O2) was the dominant reactive oxygen species for the oxidation of organic pollutants in high-salinity systems, which is less susceptible to hindrance by background constituents in wastewater than radicals(·OH or SO4·-).The surface hydroxylation of the catalyst and catalytic redox cycle including Cu and Fe are responsible for the generation of1O2.The developed Mag-CuO catalyst shows good application prospects for the removal of organic pollutants from saline wastewater.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
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 effects of chloride anion (Cl-) (up to 1.0 mol/L) on the decolorization of a model compound,azo dye Acid Orange 7 (AO7),by sulfate radical (SO4-) based-peroxydisulfate (PS) or peroxymonosulfate (PMS) o...The effects of chloride anion (Cl-) (up to 1.0 mol/L) on the decolorization of a model compound,azo dye Acid Orange 7 (AO7),by sulfate radical (SO4-) based-peroxydisulfate (PS) or peroxymonosulfate (PMS) oxidation under various activated conditions (UV 254 nm /PS,Thermal (70°C/PS,UV 254 nm /PMS,Co 2+ /PMS) were investigated.Methanol and NH4 + were used as quenching reagents to determine the contributions of active chlorine species (dichloride radical (Cl2-.) and hypochlorous acid (HClO)).The results indicated that the effects of Cl- on the reaction mechanism were different under various activated conditions.For UV/PS and Thermal/PS,the inhibition tendency became more clear as the Cl- concentration increased,probably due to the reaction between Cl- and SO4-.and the generation of Cl2-.or HClO.For UV/PMS,Cl- did not exhibit inhibition when the concentration was below 0.1 mol/L.As Cl- concentration reached to 1.0 mol/L,the decolorization rate of AO7 was,however,accelerated,possibly because PMS directly reacts with Cl- to form HClO.For Co2+ /PMS,Cl- exhibited a significant inhibiting effect even at low concentration ( 0.01 mol/L).When Cl- concentration exceeded 0.1 mol/L,the activation of PMS by Co 2+ was almost completely inhibited.Under this condition,HClO maybe played a major role in decolorization of AO7.The results implicated that chloride ion is an important factor in SO4-.-based degradation of organic contamination in chloride-containing water.展开更多
基金supported by the Sichuan Science and Technology Program(No.2021YJ0385)the Project in Yangtze River Ecological Environment Protection and Restoration(No.2022-LHYJ-02-0509-08).
文摘Dissolved copper and iron ions are regarded as friendly and economic catalysts for peroxymonosulfate(PMS)activation,however,neither Cu(Ⅱ)nor Fe(Ⅲ)shows efficient catalytic performance because of the slow rates of Cu(Ⅱ)/Cu(Ⅰ)and Fe(Ⅲ)/Fe(Ⅱ)cycles.Innovatively,we observed a significant enhancement on the degradation of organic contaminants when Cu(Ⅱ)and Fe(Ⅲ)were coupled to activate PMS in borate(BA)buffer.The degradation efficiency of Rhodamine B(RhB,20μmol/L)reached up to 96.3%within 10 min,which was higher than the sum of individual Cu(Ⅱ)-and Fe(Ⅲ)-activated PMS process.Sulfate radical,hydroxyl radical and high-valent metal ions(i.e.,Cu(Ⅲ)and Fe(IV))were identified as the working reactive species for RhB removal in Cu(Ⅱ)/Fe(Ⅲ)/PMS/BA system,while the last played a predominated role.The presence of BA dramatically facilitated the reduction of Cu(Ⅱ)to Cu(Ⅰ)via chelating with Cu(Ⅱ)followed by Fe(Ⅲ)reduction by Cu(Ⅰ),resulting in enhanced PMS activation by Cu(Ⅰ)and Fe(Ⅱ)as well as accelerated generation of reactive species.Additionally,the strong buffering capacity of BA to stabilize the solution pH was satisfying for the pollutants degradation since a slightly alkaline environment favored the PMS activation by coupling Cu(Ⅱ)and Fe(Ⅲ).In a word,this work provides a brand-new insight into the outstanding PMS activation by homogeneous bimetals and an expanded application of iron-based advanced oxidation processes in alkaline conditions.
基金University Synergy Innovation Program of Anhui Province(GXXT-2022-083)Science and Technology Plan Project of Wuhu City,China(2023kx12)Anhui Provincial Department of Education New Era Education Project(2023xscx070)。
文摘Owing to outstanding hydrophilicity and ionic interaction,layered double hydroxides(LDHs)have emerged as a promising carrier for high performance catalysts.However,the synthesis of new specialized catalytic LDHs for degradation of antibiotics still faces some challenges.In this study,a CoFe_(2)O_(4)/MgAl-LDH composite catalyst was synthesized using a hydrothermal coprecipitation method.Comprehensive characterization reveals that the surface of MgAl-LDH is covered with nanometer CoFe_(2)O_(4) particles.The specific surface area of CoFe_(2)O_(4)/MgAl-LDH is 82.84 m^(2)·g^(-)1,which is 2.34 times that of CoFe_(2)O_(4).CoFe_(2)O_(4)/MgAl-LDH has a saturation magnetic strength of 22.24 A·m^(2)·kg^(-1) facilitating efficient solid-liquid separation.The composite catalyst was employed to activate peroxymonosulfate(PMS)for the efficient degradation of tetracycline hydrochloride(TCH).It is found that the catalytic performance of CoFe_(2)O_(4)/MgAl-LDH significantly exceeds that of CoFe_(2)O_(4).The maximum TCH removal reaches 98.2%under the optimal conditions([TCH]=25 mg/L,[PMS]=1.5 mmol/L,CoFe_(2)O_(4)/MgAl-LDH=0.20 g/L,pH 7,and T=25℃).Coexisting ions in the solution,such as SO_(4)^(2-),Cl-,H_(2)PO_(4)^(-),and CO_(3)^(2-),have a negligible effect on catalytic performance.Cyclic tests demonstrate that the catalytic performance of CoFe_(2)O_(4)/MgAl-LDH remains 67.2%after five cycles.Mechanism investigations suggest that O_(2)^(•-)and ^(1)O_(2) produced by CoFe_(2)O_(4)/MgAl-LDH play a critical role in the catalytic degradation.
基金supported by the Natural Science Foundation Project of Jilin Province(Nos.20230101297JC,YDZJ202201ZYTS347,YDZJ202101ZYTS073,20210101117JC,YDZJ202201ZYTS349,YDZJ202102CXJD049)the National Natural Science Foundation(22004047)+4 种基金China Postdoctoral Science Foundation(No.2023M731299)the Project of Jilin Province Development and Reform Commission(Nos.2023C032-5,2023C032-4,2023C032-2)the Project of Human Resources and Social Security Department of Jilin Province(No.2023337)the National College students’innovation and entrepreneurship training program(No.202310203008)the Project of Education Department of Jilin Province(Nos.JJKH20220429KJ,JJKH20210460KJ).
文摘Integrating photocatalysis technology with peroxymonosulfate oxidation possesses huge potential for degrading stubborn pollutant.Herein,a porous ultra-thin carbon nitride with C-defect O-doping and advanced n-π^(∗)transition was customized by one-pot thermalinduced polymerization of molten urea assisted with paraformaldehyde.Via visible-light coupling peroxymonosulfate activation,the DCN-100 can completely photodegrade 2,4-dichlorophenol,and rate constant is 136.6 and 37.9 times that of CN and DCN-100 without peroxymonosulfate.The light-absorption of DCN-100 surpasses 550 nm,specific surface area rises from 45.03 to 98.58m^(2)/g,and charge behaviors are significantly improved.The effects of paraformaldehyde amount,PMS dosage,pH,2,4-dichlorophenol concentration,different water-body,wavelength and recycling times on photodegradation performance were explored in detail.Via capture experiments,ESR,LC-MS,Fukui-function,TEXT toxicity assessment and DFT theoretical calculation,themain active substances,degradation pathway,intermediate toxicity and enhanced activity mechanism of DCN-100 were clarified.The research provides a cost-effective,high-efficiency and environmental-friendly photocatalysts to activate peroxymonosulfate for water remediating.
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.
基金financially supported by the National Key Research and Development Program of China(No.2022YFC3703103)National Natural Science Foundation of China(Nos.22206053,42277427)the Guangzhou Science and Technology Plan Project(No.2024A04J4058)。
文摘Bisphenol A(BPA)has threatened ecological safety and human health due to its endocrine disrupting effect and widely diffused in the environment.Peroxymonosulfate(PMS)based on oxidation technology exhibits good potential for environmental remediation whereas the highly efficient activator needs to be developed.Herein,the Bi OBr(BOB)was synthesized to efficiently activate PMS to remove 95.6%of BPA within 60 min.The observed rate constant of BPA removal in BOB/PMS system is 0.049 min^(-1),which is 60 and 148 times to that of the BOB and PMS processes separately and 129 times to the compared Bi OCl(BOC)/PMS system,respectively.Comparison experiments and analytic methods demonstrate that BOB with a larger content of oxygen vacancies(Ov)can act as the bridge of electron transfer between Bi^(3+)/Bi^(4+)with PMS to enhance the activation ability for PMS,resulting in the production of abundant reactive oxygen species(O_(2)^(·-)and ^(1)O_(2)).Additionally,the breakdown processes of BPA and the toxicity of its byproducts were uncovered,and the potential for actual water treatment was evaluated to confirm the detoxification,efficiency,stability and practical use of the BOB/PMS system for eliminating BPA.This study may widen the application of traditional semiconductors and develop the cost-effective PMS activation methods for environmental remediation.
基金the financial support from Sichuan Science and Technology Program(No.2023NSFSC0847)Scientific Research and Innovation Team Program of Sichuan University of Science and Technology(No.SUSE652A003)+3 种基金Talent Introduction Project of Sichuan University of Science and Engineering(No.2021RC03)Talent Introduction Project of Sichuan University of Science and Engineering(No.2021RC05)the Undergraduate Training Program for Innovation and Entrepreneurship(No.CX2024042)The Innovation Fund of Postgraduate,Sichuan University of Science&Engineering(No.Y2024094)。
文摘N-doped graphite carbon sphere coated cobalt nanoparticle catalyst(Co@C-N-900),prepared by solvothermal-calcination method,is applied to activate peroxymonosulfate(PMS)for bisphenol A(BPA)elimination.The outcomes demonstrate that the Co@C-N-900 could effectively activate PMS,thereby causing efficient removal of BPA in water.In addition,the Co@C-N-900/PMS system also has the advantages of low metal leaching,applicability in high salinity environments,good selectivity and stability.Further investigations using electron paramagnetic resonance,chronoamperometry,and quenching experiments demonstrated that the Co@C-N-900/PMS system is a typical non-radical route with singlet oxygen(^(1)O_(2))as the main reactive oxygen species(ROS).Density functional theory calculations(DFT)indicate that N-doping can effectively regulate the charge distribution on the catalyst surface,generating acidic/alkaline sites favorable for PMS adsorption and activation.Furthermore,it also can enhance the interaction and charge transfer capacity between the Co@C-N-900 and PMS.Lastly,LC-QTOF-MS/MS analysis revealed two possible BPA degradation pathways:(1)^(1)O_(2)attacked the isopropyl group in BPA between the two phenyl groups,causingβ-scission to occur.(2)Following the oxidation of the hydroxyl group in the aromatic ring of BPA,^(1)O_(2)could cause furtherβ-scission.The prepared Co@C-N-900 catalyst is a very promising catalyst,which would offer a workable remedy for treating water pollution.
基金Project(23-2-1-107-zyyd-jch)supported by the Qingdao Natural Science Foundation,ChinaProject(ZR2022QE236)supported by the Natural Science Foundation of Shandong Province Youth Project,China+2 种基金Project(SDCX-ZG-202400211,SDCX-ZG-202203052)supported by the Shandong Postdoctoral Science Foundation,ChinaProject(ZD2023K03)supported by the Engineering Research Center of Non-metallic Minerals of Zhejiang Province,ChinaProject(01020240806)supported by the Qingdao Postdoctoral Program for Applied Research,China。
文摘Developing a low-cost stable and high-performance peroxymonosulfate(PMS)catalyst to degrade refractory organic pollutants is still an urgent problem.Herein,this study reported FeVO_(4)nanorods decorated sepiolite(FeVO_(4)/sepiolite)through simple hydrothermal method as an adsorptive-catalyst for PMS activation to degrade tetracycline(TC).Benefiting from the introduction of sepiolite support,FeVO_(4)nanorods could be uniformly immobilized onto fibrous sepiolite surface.As a result,FeVO_(4)/sepiolite composite was endowed with excellent adsorption properties,rich surface hydroxyl groups,more reaction active sites,and the stable redox cycle of Fe^(3+)/Fe^(2+)and V5^(+)/V4^(+).Therefore,higher TC degradation efficiency(91.19%within 40 min)and larger reaction rate constant(0.1649 min^(-1))were obtained in FeVO_(4)/sepiolite/PMS system than in FeVO_(4)/PMS system.Besides,the composite presented good stability and reusability,and the effects of application parameters on TC degradation were investigated in detail.Through quenching experiment and electron paramagentic resonance(EPR)test,it was found that both radical and non-radical species participates in TC degradation,and ^(1)O_(2) were the main active species.The PMS activation mechanism was proposed,and the possible degradation pathway was also analyzed according to the high performance liquid chromatography-mass spectrometry(HPLC-MS)results.Overall,this work provides meaningful insights for designing natural mineral based PMS activators to effectively remediate antibiotic wastewater.
基金supported by the National Natural Science Foundation of China(NSFC)(No.21978137).
文摘In this study,supported Pd catalysts were prepared and used as heterogeneous catalysts for the activation of peroxymonosulfate(PMS)which successfully degrade bisphenol F(BPF).Among the supported catalysts(i.e.,Pd/SiO_(2),Pd/CeO_(2),Pd/TiO_(2)and Pd/Al2O3),Pd/TiO_(2)exhibited the highest catalytic activity due to the high isoelectric point and high Pd0 content.Pd/TiO_(2)prepared by the deposition method leads to high Pd dispersion,which are the key factors for efficient BPF degradation.The influencing factors were investigated during the reaction process and two possible degradation pathways were proposed.Density functional theory(DFT)calculations demonstrate that stronger BPF adsorption and BPF degradation with lower reaction barrier occurs on smaller Pd particles.The catalytic activities are strongly dependent on the structural features of the catalysts.Both experiments and theoretical calculations prove that the reaction is actuated by electron transfer rather than radicals.
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.52100087,52170079,U20A20322)Science and Technology Development Program of Jilin Province,China(Nos.20220508100RC,20230402035GH).
文摘Rational tuning of crystallographic surface and metal doping were effective to enhance the catalytic performance of metal organic frameworks,but limited work has been explored for achieving modulation of crystal facets and metal doping in a single system.MIL-68(In)was promising for photocatalytic applications due to its low toxicity and excellent photoresponsivity.However,its catalytic activity was constrained by severe carrier recombination and a lack of active sites.Herein,increased(001)facet ratio and active sites exposure were simultaneously realized by cobalt doping in MIL-68(In)through a one-pot solvothermal strategy.Optimized MIL-68(In/Co)-2.5 exhibited remarkable catalytic performance in comparison with pristine MIL-68(In)and other MIL-68(In/Co).The reaction kinetic constant and degradation efficiency of MIL-68(In/Co)were approximately twice and 17%higher than the pristine MIL-68(In)in 36 min reaction,respectively.Density functional theory calculations revealed that Co dopant could modulate the orientation of MIL-68(In)facets,facilitate the exchange of electrons and reduce the adsorption energy of peroxymonosulfate(PMS).This work provides a novel pathway for improvement of In-based MOFs in PMS/vis system,it also promotes the profound comprehension of the correlation between crystal facet regulation and catalytic activation in the PMS/vis system.
基金supported by the National Natural Science Foundation of China(Nos.22076052 and 21976063)China Postdoctoral Science Foundation(No.2018M642850)the Research Funding of Wuhan Polytechnic University(No.2023RZ017).
文摘An efficient catalytic system was developed to remove various organic pollutants by simultaneously using low-level cobalt ions,calcium carbonate micro-particles and peroxymonosulfate(PMS).A simple base-induced precipitation was used to successfully loaded Co-centered reactive sites onto the surface of CaCO_(3)microparticles.Under optimal conditions at 25°C,10 mg/L methylene blue(MB)could be completely degraded within 10 min with 480μg/L Co^(2+),0.4 g/L CaCO_(3)microparticles(or 0.4 g/L Co@CaCO_(3))and 0.1 g/L PMS.The MB degradation followed the pseudo first order kinetics with a rate constant of 0.583 min^(−1),being 8.3,11.5 and 53.0 times that by using Co-OH(0.07 min^(−1)),Co^(2+)(0.044 min^(−1))and CaCO_(3)(0.011 min^(−1))as the catalyst,respectively.It was confirmed that there was a synergistic effect in the catalytic activity between Co species and the CaCO_(3)particles but the major contributor was the highly dispersed Co species.When Co^(2+)-containing simulated electroplating wastewater was used as the Co^(2+)source,not only the added MB was also completely degraded within 5 min in this catalytic system,but also the coexisting heavy metal ions were substantially removed.The presently developed method was applied to simultaneously treat organic wastewater and heavy metals wastewater.The present method was also successfully used to efficiently degrade other organic pollutants including bisphenol A,sulfamethoxazole,rhodamine B,tetrabromobisphenol A,ofloxacin and benzoic acid.A catalytic mechanism was proposed for the PMS activation by Co@CaCO_(3).The surface of CaCO_(3)particles favors the adsorption of Co^(2+).More importantly,the surface of CaCO_(3)particles provides plentiful surface-OH and-CO_(3)^(2+),and these surface groups complex with Co^(2+)to producemore catalytically active species such as surface[CoOH]^(−),resulting in rapid Co^(2+)/Co^(3+)cycling and electron transfer.These interactions cause the observed synergistic effect between Co species and CaCO_(3)particles in PMS activation.Due to good cycle stability,strong anti-interference ability and wide universality,the new method will have broad application prospects.
基金the financial support from Sichuan Program of Science and Technology(No.2021ZDZX0012)the National Natural Science Foundation of China(No.52200105)。
文摘The contamination of water resources by phenolic compounds(PCs)presents a significant environmental hazard,necessitating the development of novel materials and methodologies for effective mitigation.In this study,a metallic copper-doped zeolitic imidazolate framework was pyrolyzed and designated as CuNC-20 for the activation of peroxymonosulfate(PMS)to degrade phenol(PE).Cu-NC-20 could effectively address the issue of metal agglomeration while simultaneously diminishing copper dissolution during the activation of PMS reactions.The Cu-NC-20 catalyst exhibited a rapid degradation rate for PE across a broad pH range(3-9)and demonstrated high tolerance towards coexisting ions.According to scavenger experiments and electron paramagnetic resonance analysis,singlet oxygen(^(1)O_(2))and high-valent copperoxo(Cu(Ⅲ))were the predominant reactive oxygen species,indicating that the system was nonradicaldominated during the degradation process.The quantitative structure-activity relationship(QSAR)between the oxidation rate constants of various substituted phenols and Hammett constants was established.It indicated that the Cu-NC-20/PMS system had the optimal oxidation rate constant withσ^(-)correlation and exhibited a typical electrophilic reaction pattern.This study provides a comprehensive understanding of the heterogeneous activation process for the selective removal of phenolic compounds.
基金financial support from the National Natural Science Foundation of China(Nos.22276159,J2224005)the Key research project plan for higher education institutions of Henan province(No.24ZX009)+1 种基金the Development Program for Key Young Teachers in Colleges and Universities of Henan Province(No.2020GGJS146)the Starting Research Fund of Xinxiang Medical University(No.XYBSKYZZ201911)。
文摘In this work,atomic Co catalysts are anchored on a three-dimensional(3D)interconnected g-C_(3)N_(4)(SACo-CN)through Co-N coordination,which exhibit efficient charge carrier transition and low activation energy barriers for peroxymonosulfate(PMS).The incorporation of Co atoms extends the absorption spectrum and enhances the photoelectron-hole separation efficiency of the SACo-CN samples.The 3D interconnected structure,combined with the synergistic interplay between Co-N coordination and visible light irradiation,results in SACo-CN catalysts demonstrating excellent catalytic activity and stability for PMS activation.This leads to a degradation rate of 98.8%for oxytetracycline(OTC)within 30 min under visible light.The research proposes three potential mineralization pathways with eight intermediates,leading to a significant decrease in the toxicity of the intermediates.This work provides a facile and promising approach for the preparation of metal single atom catalysts with highly efficient PMS activation performance.
基金financially supported by the National Natural Science Foundation of China(52063024 and 51868052)the Natural Science Foundation of Jiangxi Province(20192ACBL21046)the National Science Foundation of State Key Laboratory of Structural Chemistry(20160013).
文摘The degradation of organic pollutants in water is a critical environmental challenge.The iron-doped MoS_(2) catalysts have demonstrated potential in activating peroxymonosulfate(PMS)for environmental remediation,but they face challenges such as poor conductivity,limited electron transfer efficiency,and a scarcity of active sites.To address these issues,we successfully synthesized a nano-flowers FeS/MoS_(2) composite derived from polyoxometalates(NH_(4))_(3)[Fe(III)Mo_(6)O_(24)H_(6)]⋅6H_(2)O(denoted as FeMo6)as the bimetallic precursors.This synthesis strategy enhances the interaction between FeS and MoS_(2),thereby facilitating electron transfer.Notably,the introduction of sulfur vacancies in FeS/MoS_(2) exposes additional Mo4t active sites,promoting the redox cycle of Fe^(2+)/Fe^(3+) and accelerating the regeneration of Fe^(2+),which in turn enhances PMS activation.Therefore,a catalytic oxidation system of FeS/MoS_(2)/PMS is presented that primarily relies on SO_(4)^(⋅-)and⋅OH,with ^(1)O_(2) as a supplementary oxidant.This system exhibits exceptional degradation efficiency for p-chlorophenol(4-CP),achieving 100% degradation within 10 min over a wide pH range of 2.4–8.4.The robust performance and wide applicability of FeS/MoS_(2) catalyst make it a promising candidate in advanced oxidation processes(AOPs)for environmental remediation.
基金supported by the National Natural Science Foundation of China (21377169, 21507168)the Fundamental Research Funds for the Central Universities (CZW15078)the Natural Science Foundation of Hubei Province of China (2014CFC1119, 2015CFB505)~~
文摘Magnetic Cu^0/Fe3O4 submicron composites were prepared using a hydrothermal method and used as heterogeneous catalysts for the activation of peroxymonosulfate(PMS) and the degradation of organic pollutants.The as-prepared magnetic Cu^0/Fe3O4 submicron composites were composed of Cu^0 and Fe3O4 crystals and had an average size of approximately 220 nm.The Cu^0/Fe3O4 composites could efficiently catalyze the activation of PMS to generate singlet oxygen,and thus induced the rapid degradation of rhodamine B,methylene blue,orange Ⅱ,phenol and 4-chlorophenol.The use of0.1 g/L of the Cu^0/Fe3O4 composites induced the complete removal of rhodamine B(20 μmol/L) in15 min,methylene blue(20 μmol/L) in 5 min,orange Ⅱ(20 μmol/L) in 10 min,phenol(0.1mmol/L) in 30 min and 4-chlorophenol(0.1 mmol/L) in 15 min with an initial pH value of 7.0 and a PMS concentration of 0.5 mmol/L.The total organic carbon(TOC) removal higher than 85%for all of these five pollutants was obtained in 30 min when the PMS concentration was 2.5 mmol/L.The rate of degradation was considerably higher than that obtained with Cu^0 or Fe3O4 particles alone.The enhanced catalytic activity of the Cu^0/Fe3O4 composites in the activation of PMS was attributed to the synergistic effect of the Cu^0 and Fe3O4 crystals in the composites.Singlet oxygen was identified as the primary reactive oxygen species responsible for pollutant degradation by electron spin resonance and radical quenching experiments.A possible mechanism for the activation of PMS by Cu^0/Fe3O4 composites is proposed as electron transfer from the organic pollutants to PMS induces the activation of PMS to generate ^1O2,which induces the degradation of the organic pollutants.As a magnetic catalyst,the Cu^0/Fe3O4 composites were easily recovered by magnetic separation,and exhibited excellent stability over five successive degradation cycles.The present study provides a facile and green heterogeneous catalysis method for the oxidative removal of organic pollutants.
基金financially supported by the National Natural Science Foundation of China(No.22006052)the Science and Technology Program of Guangzhou,China(No.202201020545)。
文摘The adsorption of peroxymonosulfate(PMS)is crucial for PMS activation in the heterogeneous advanced oxidation processes.However,the investigation of PMS adsorption on the piezocatalysts still remains insufficient.In this work,bismuth oxychloride(BiO Cl)nanosheets were prepared as the piezocatalysts for PMS activation under ultrasonic vibration to remove carbamazepine(CBZ)in aqueous solutions.Up to92.5%of CBZ was degraded for 40 min in Bi OCl piezo-activated PMS system with the reaction rate constant of 0.0741 min-1,being 1.63 times that of the sum of BiOCl piezocatalysis,BiOCl-activated PMS,and vibration-activated PMS.PMS adsorption on the surface of BiOCl was specifically studied by comparing the microscopic structure change of the fresh and used Bi OCl.The results suggested that the piezoelectric field of Bi OCl was able to promote the tight adsorption of PMS on the surface,thus facilitating the fast activation of PMS through electrons transfer to produce reactive species(HO·,SO_(4)·-,O_(2)·-,1O_(2)).This work presents an in-depth understanding for the role of piezoelectric effect on the adsorption and activation of PMS.
基金supported by the National Water Pollution Control and Management Program of China (No.2017ZX07107002).
文摘Magnetic CuO nanosheet(Mag-CuO), as a cheap, stable, efficient and easily separated peroxymonosulfate(PMS) activator, was prepared by a simple one-step precipitation method for the removal of organic compounds from salt-containing wastewater.The experiments showed that the removal efficiencies of various organic pollutants including Acid Orange 7, Methylene Blue, Rhodamine B and atrazine in a high-salinity system(0.2 mol/L Na2SO4) with the Mag-CuO/PMS process were 95.81%, 74.57%, 100% and 100%,respectively.Meanwhile, Mag-CuO still maintained excellent catalytic activity in other salt systems including one or more salt components(NaCl, NaNO3, Na2HPO4, NaHCO3).A radical-quenching study and electron paramagnetic resonance analysis confirmed that singlet oxygen(1O2) was the dominant reactive oxygen species for the oxidation of organic pollutants in high-salinity systems, which is less susceptible to hindrance by background constituents in wastewater than radicals(·OH or SO4·-).The surface hydroxylation of the catalyst and catalytic redox cycle including Cu and Fe are responsible for the generation of1O2.The developed Mag-CuO catalyst shows good application prospects for the removal of organic pollutants from saline wastewater.
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 (No. 21107101)the Fundamental Research Funds for the Central Universities of China (Ocean University of China)(No.201113005)
文摘The effects of chloride anion (Cl-) (up to 1.0 mol/L) on the decolorization of a model compound,azo dye Acid Orange 7 (AO7),by sulfate radical (SO4-) based-peroxydisulfate (PS) or peroxymonosulfate (PMS) oxidation under various activated conditions (UV 254 nm /PS,Thermal (70°C/PS,UV 254 nm /PMS,Co 2+ /PMS) were investigated.Methanol and NH4 + were used as quenching reagents to determine the contributions of active chlorine species (dichloride radical (Cl2-.) and hypochlorous acid (HClO)).The results indicated that the effects of Cl- on the reaction mechanism were different under various activated conditions.For UV/PS and Thermal/PS,the inhibition tendency became more clear as the Cl- concentration increased,probably due to the reaction between Cl- and SO4-.and the generation of Cl2-.or HClO.For UV/PMS,Cl- did not exhibit inhibition when the concentration was below 0.1 mol/L.As Cl- concentration reached to 1.0 mol/L,the decolorization rate of AO7 was,however,accelerated,possibly because PMS directly reacts with Cl- to form HClO.For Co2+ /PMS,Cl- exhibited a significant inhibiting effect even at low concentration ( 0.01 mol/L).When Cl- concentration exceeded 0.1 mol/L,the activation of PMS by Co 2+ was almost completely inhibited.Under this condition,HClO maybe played a major role in decolorization of AO7.The results implicated that chloride ion is an important factor in SO4-.-based degradation of organic contamination in chloride-containing water.