Ferromagnetic Fe3O4 nanoparticles were synthesized using water as the solvent through the sol-gel method, which was selected for its cost-effectiveness, simplicity, and eco-friendly nature. The synthesized nanoparticl...Ferromagnetic Fe3O4 nanoparticles were synthesized using water as the solvent through the sol-gel method, which was selected for its cost-effectiveness, simplicity, and eco-friendly nature. The synthesized nanoparticles were characterized using a variety of techniques, including Fourier Transform Infrared (FTIR) spectroscopy, X-ray powder diffraction (XRD), Scanning Electron Microscopy (SEM), Thermogravimetric Analysis (TGA), and Vibrating Sample Magnetometer (VSM). These characterizations confirmed the successful formation of Fe3O4 nanoparticles. The FTIR spectra identified characteristic peaks corresponding to the functional groups present, and XRD analysis, using Scherer’s equation, determined an average crystalline size of 1.2 nm for the Fe3O4 nanoparticles. TGA results demonstrated the thermal stability of the nanoparticles, SEM imaging revealed distinct honeycomb-like structures for the nanoparticles synthesized with water as the solvent, while the VSM analysis was used to determine the magnetic behavior of the nanoparticles.展开更多
Due to its high efficiency,Fe(Ⅱ)-based catalytic oxidation has been one of the most popular types of technology for treating growing organic pollutants.A lot of chemical Fe sludge alongwith various refractory polluta...Due to its high efficiency,Fe(Ⅱ)-based catalytic oxidation has been one of the most popular types of technology for treating growing organic pollutants.A lot of chemical Fe sludge alongwith various refractory pollutantswas concomitantly produced,whichmay cause secondary environmental problemswithout proper disposal.We here innovatively proposed an effective method of achieving zero Fe sludge,reusing Fe resources(Fe recovery=100%)and advancing organics removal(final TOC removal>70%)simultaneously,based on the in situ formation of magnetic Ca-Fe layered double hydroxide(Fe_(3)O_(4)@CaFe-LDH)nano-material.Cations(Ca^(2+)and Fe^(3+))concentration(≥30 mmol/L)and their molar ratio(Ca:Fe≥1.75)were crucial to the success of the method.Extrinsic nano Fe_(3)O_(4)was designed to be involved in the Fe(Ⅱ)-catalytic wastewater treatment process,and was modified by oxidation intermediates/products(especially those with COO-structure),which promoted the co-precipitation of Ca^(2+)(originated from Ca(OH)_(2)added after oxidation process)and byproduced Fe^(3+)cations on its surface to in situ generate core-shell Fe_(3)O_(4)@CaFe-LDH.The oxidation products were further removed during Fe_(3)O_(4)@CaFe-LDH material formation via intercalation and adsorption.Thismethodwas applicable to many kinds of organicwastewater,such as bisphenol A,methyl orange,humics,and biogas slurry.The prepared magnetic and hierarchical CaFe-LDH nanocomposite material showed comparable application performance to the recently reported CaFe-LDHs.This work provides a new strategy for efficiently enhancing the efficiency and economy of Fe(Ⅱ)-catalyzed oxidative wastewater treatment by producing high value-added LDHs materials.展开更多
Herein,an oxygen-doped porous g-C_(3)N_(4)photocatalyst modified with atomically dispersed Fe(Fe_(1)/OPCN)issuccessfully prepared and exhibits significant superiority in removing refractory sulfonic azo contaminants f...Herein,an oxygen-doped porous g-C_(3)N_(4)photocatalyst modified with atomically dispersed Fe(Fe_(1)/OPCN)issuccessfully prepared and exhibits significant superiority in removing refractory sulfonic azo contaminants fromwater via catalyst-contaminant interaction.The elimination performance of Fe_(1)/OPCN towards acid red 9,acidred 13 and amaranth containing similar azonaphthalene structure and increasing sulfonic acid groups increasesgradually.The amaranth degradation rate of Fe_(1)/OPCN is 17.7 and 6.1 times as that of homogeneous Fenton andOPCN,respectively.In addition,Fe_(1)/OPCN also has more outstanding removal activities towards other con-taminantswith sulfonic acid and azo groups alone.The considerable enhancement for removing sulfonic azocontaminants of Fe_(1)/OPCN is mainly ascribed to the following aspects:(1)The modified Fe could enhance theadsorption towards sulfonic azo compounds to accelerate the mass transfer,act as e^(-)acceptor to promoteinterfacial charge separation,and trigger the self-Fenton reaction to convert in-situ generated H_(2)O_(2)into·OH.(2)Fe(Ⅲ)could coordinate with-N=N-to form d-πconjugation,which could attract e^(-)transfer to attack-N=N-bond.Meanwhile,the inhibited charge recombination could release more free h^(þ)to oxidize sulfonicacid groups into SO4^(-)·.(3)Under the cooperation of abundant multiple active species(·O_(2)^(-),h^(þ),e^(-),·OH,SO4^(-)·)formed during the degradation reaction,sulfonic azo compounds could be completely mineralized into harmlesssmall molecules(CO_(2),H_(2)O,etc.)by means of-N=N-cleavage,hydroxyl substitution,and aromatic ringopening.This work offers a novel approach for effectively eliminating refractory sulfonic azo compounds fromwastewater.展开更多
Regulating the orbital spin-electron filling of metal centers via interatomic electron transfer in transition metal oxides is one promising approach to enhancing their electrocatalytic oxygen evolution reaction(OER)pe...Regulating the orbital spin-electron filling of metal centers via interatomic electron transfer in transition metal oxides is one promising approach to enhancing their electrocatalytic oxygen evolution reaction(OER)performances,while it is still a challenge due to lacking of efficient strategy and deep understanding.In this work,a facile strategy containing electrochemical deposition and annealing in air atmosphere has been proposed to introduce monodispersed neodymium(Nd)atoms into spinel Co_(3)O_(4)nanosheets to trigger the electron transfer.Accordingly,the as-prepared Nd doped Co_(3)O_(4)nanosheets(Nd/Co_(3)O_(4))on nickel foam or carbon cloth showed greatly enhanced OER performances,with low overpotential of 284 and 396 mV at 10 m A cm^(-2),small Tafel slope of 95 and 119 mV dec^(-1)in 1.0 M KOH and 0.5 M H_(2)SO_(4),respectively.The experimental and density function theory results coherently indicate that the charge transfer in the Nd-O-Co asymmetric configuration not only enhances the conductivity of Co_(3)O_(4),but also regulates the filling degree of egorbitals of Co,leading to higher spin states,optimized adsorption ability,and accelerated H_(2)O dissociation process,thus achieving boosted OER activity.展开更多
To remove the fluoride in zinc sulfate electrolyte to an appropriate level,mitigate environmental fluoride pollution,and drive the development of the hydrometallurgy industry of zinc,a novel Fe_(3)O_(4)@SiO_(2)@Fe-MIL...To remove the fluoride in zinc sulfate electrolyte to an appropriate level,mitigate environmental fluoride pollution,and drive the development of the hydrometallurgy industry of zinc,a novel Fe_(3)O_(4)@SiO_(2)@Fe-MIL-101 magnetic composite material was successfully synthesized via the one-pot method.Preparation conditions were optimized and structural characterization of this material conducted using FTIR,SEM,EDS,XRD and Hysteresis analysis.The results show that this composite exhibits a more rapid fluoride adsorption dynamics and a higher fluoride adsorption capacity(18.34 mg/g)and its adsorption behavior fitted for the first order dynamic model and the Freundlich isotherm model.The adsorption of fluorine by this composite is mainly physical adsorption according to the mean adsorption energy(1.216 kJ/mol).The interfering ions co-existed in fluoride-containing solutions,like HCO_(3)^(-),NO^(-)and Cl^(-),have a significant effect on fluorine adsorption.This composite has also been proved with magnetism,higher adsorption selectivity and satisfactory reusability.When this composite is employed as an adsorbent for adsorption removing fluoride in zinc sulfate electrolyte,it exhibits higher pH-dependent behavior as well as high fluoride removal efficiency at pH 6.5.展开更多
As BiVO4 is one of the most popular visible-light-responding photocatalysts, it has been widely used for visiblelight-driven water splitting and environmental purification. However, the typical photocatalytic activity...As BiVO4 is one of the most popular visible-light-responding photocatalysts, it has been widely used for visiblelight-driven water splitting and environmental purification. However, the typical photocatalytic activity of unmodified BiVO4 for the degradation of organic pollutants is still not impressive. To address this limitation, we studied Fe2O3-modified porous BiVO4 nanoplates. Compared with unmodified BiVO4, the Fe2O3-modified porous Bi VO4 nanoplates showed significantly enhanced photocatalytic activities in decomposing both dye and colorless pollutant models, such as rhodamine B(Rh B) and phenol,respectively. The pseudo-first-order reaction rate constants for the degradation of RhB and phenol on Fe2O3-modified BiVO4 porous nanoplates are 27 and 31 times larger than that of pristine Bi VO4, respectively. We also found that the Fe2O3 may act as an efficient non-precious metal co-catalyst, which is responsible for the excellent photocatalytic activity of Fe2O3/BiVO4.Graphical Abstract Fe2O3, as a cheap and efficient co-catalyst, could greatly enhance the photocatalytic activity of Bi VO4 porous nanoplates in decomposing organic pollutants.展开更多
文摘Ferromagnetic Fe3O4 nanoparticles were synthesized using water as the solvent through the sol-gel method, which was selected for its cost-effectiveness, simplicity, and eco-friendly nature. The synthesized nanoparticles were characterized using a variety of techniques, including Fourier Transform Infrared (FTIR) spectroscopy, X-ray powder diffraction (XRD), Scanning Electron Microscopy (SEM), Thermogravimetric Analysis (TGA), and Vibrating Sample Magnetometer (VSM). These characterizations confirmed the successful formation of Fe3O4 nanoparticles. The FTIR spectra identified characteristic peaks corresponding to the functional groups present, and XRD analysis, using Scherer’s equation, determined an average crystalline size of 1.2 nm for the Fe3O4 nanoparticles. TGA results demonstrated the thermal stability of the nanoparticles, SEM imaging revealed distinct honeycomb-like structures for the nanoparticles synthesized with water as the solvent, while the VSM analysis was used to determine the magnetic behavior of the nanoparticles.
基金supported by the Chinese Agriculture Research System(No.CARS-35-06B)111 Project(No.B17030)the Sichuan Science and Technology Program(No.2021ZDZX0012).
文摘Due to its high efficiency,Fe(Ⅱ)-based catalytic oxidation has been one of the most popular types of technology for treating growing organic pollutants.A lot of chemical Fe sludge alongwith various refractory pollutantswas concomitantly produced,whichmay cause secondary environmental problemswithout proper disposal.We here innovatively proposed an effective method of achieving zero Fe sludge,reusing Fe resources(Fe recovery=100%)and advancing organics removal(final TOC removal>70%)simultaneously,based on the in situ formation of magnetic Ca-Fe layered double hydroxide(Fe_(3)O_(4)@CaFe-LDH)nano-material.Cations(Ca^(2+)and Fe^(3+))concentration(≥30 mmol/L)and their molar ratio(Ca:Fe≥1.75)were crucial to the success of the method.Extrinsic nano Fe_(3)O_(4)was designed to be involved in the Fe(Ⅱ)-catalytic wastewater treatment process,and was modified by oxidation intermediates/products(especially those with COO-structure),which promoted the co-precipitation of Ca^(2+)(originated from Ca(OH)_(2)added after oxidation process)and byproduced Fe^(3+)cations on its surface to in situ generate core-shell Fe_(3)O_(4)@CaFe-LDH.The oxidation products were further removed during Fe_(3)O_(4)@CaFe-LDH material formation via intercalation and adsorption.Thismethodwas applicable to many kinds of organicwastewater,such as bisphenol A,methyl orange,humics,and biogas slurry.The prepared magnetic and hierarchical CaFe-LDH nanocomposite material showed comparable application performance to the recently reported CaFe-LDHs.This work provides a new strategy for efficiently enhancing the efficiency and economy of Fe(Ⅱ)-catalyzed oxidative wastewater treatment by producing high value-added LDHs materials.
基金supported by the Natural Science Foundation of Jiangsu Province(BK20221541)National Natural Science Foundation of China(21707052)Jiangsu Agriculture Science and Technology Innovation Fund(CX(20)3108).
文摘Herein,an oxygen-doped porous g-C_(3)N_(4)photocatalyst modified with atomically dispersed Fe(Fe_(1)/OPCN)issuccessfully prepared and exhibits significant superiority in removing refractory sulfonic azo contaminants fromwater via catalyst-contaminant interaction.The elimination performance of Fe_(1)/OPCN towards acid red 9,acidred 13 and amaranth containing similar azonaphthalene structure and increasing sulfonic acid groups increasesgradually.The amaranth degradation rate of Fe_(1)/OPCN is 17.7 and 6.1 times as that of homogeneous Fenton andOPCN,respectively.In addition,Fe_(1)/OPCN also has more outstanding removal activities towards other con-taminantswith sulfonic acid and azo groups alone.The considerable enhancement for removing sulfonic azocontaminants of Fe_(1)/OPCN is mainly ascribed to the following aspects:(1)The modified Fe could enhance theadsorption towards sulfonic azo compounds to accelerate the mass transfer,act as e^(-)acceptor to promoteinterfacial charge separation,and trigger the self-Fenton reaction to convert in-situ generated H_(2)O_(2)into·OH.(2)Fe(Ⅲ)could coordinate with-N=N-to form d-πconjugation,which could attract e^(-)transfer to attack-N=N-bond.Meanwhile,the inhibited charge recombination could release more free h^(þ)to oxidize sulfonicacid groups into SO4^(-)·.(3)Under the cooperation of abundant multiple active species(·O_(2)^(-),h^(þ),e^(-),·OH,SO4^(-)·)formed during the degradation reaction,sulfonic azo compounds could be completely mineralized into harmlesssmall molecules(CO_(2),H_(2)O,etc.)by means of-N=N-cleavage,hydroxyl substitution,and aromatic ringopening.This work offers a novel approach for effectively eliminating refractory sulfonic azo compounds fromwastewater.
基金support from the Natural Science Foundation and Overseas Talent Projects of Jiangxi Province(20242BAB25217,20232BAB214025,20232BCJ25044)the Jiangxi Provincial Natural Science Foundation(20232BAB204088)the National Natural Science Foundation of China(52402132)。
文摘Regulating the orbital spin-electron filling of metal centers via interatomic electron transfer in transition metal oxides is one promising approach to enhancing their electrocatalytic oxygen evolution reaction(OER)performances,while it is still a challenge due to lacking of efficient strategy and deep understanding.In this work,a facile strategy containing electrochemical deposition and annealing in air atmosphere has been proposed to introduce monodispersed neodymium(Nd)atoms into spinel Co_(3)O_(4)nanosheets to trigger the electron transfer.Accordingly,the as-prepared Nd doped Co_(3)O_(4)nanosheets(Nd/Co_(3)O_(4))on nickel foam or carbon cloth showed greatly enhanced OER performances,with low overpotential of 284 and 396 mV at 10 m A cm^(-2),small Tafel slope of 95 and 119 mV dec^(-1)in 1.0 M KOH and 0.5 M H_(2)SO_(4),respectively.The experimental and density function theory results coherently indicate that the charge transfer in the Nd-O-Co asymmetric configuration not only enhances the conductivity of Co_(3)O_(4),but also regulates the filling degree of egorbitals of Co,leading to higher spin states,optimized adsorption ability,and accelerated H_(2)O dissociation process,thus achieving boosted OER activity.
基金National Natural Science Foundation of China(21865011)2024 Innovation and Entrepreneurship Project of College Student in Jishou University(JDCX20241122)。
文摘To remove the fluoride in zinc sulfate electrolyte to an appropriate level,mitigate environmental fluoride pollution,and drive the development of the hydrometallurgy industry of zinc,a novel Fe_(3)O_(4)@SiO_(2)@Fe-MIL-101 magnetic composite material was successfully synthesized via the one-pot method.Preparation conditions were optimized and structural characterization of this material conducted using FTIR,SEM,EDS,XRD and Hysteresis analysis.The results show that this composite exhibits a more rapid fluoride adsorption dynamics and a higher fluoride adsorption capacity(18.34 mg/g)and its adsorption behavior fitted for the first order dynamic model and the Freundlich isotherm model.The adsorption of fluorine by this composite is mainly physical adsorption according to the mean adsorption energy(1.216 kJ/mol).The interfering ions co-existed in fluoride-containing solutions,like HCO_(3)^(-),NO^(-)and Cl^(-),have a significant effect on fluorine adsorption.This composite has also been proved with magnetism,higher adsorption selectivity and satisfactory reusability.When this composite is employed as an adsorbent for adsorption removing fluoride in zinc sulfate electrolyte,it exhibits higher pH-dependent behavior as well as high fluoride removal efficiency at pH 6.5.
基金partial financial support from NSFC(51372173,51002107,and21173159)NSFC for Distinguished Young Scholars(51025207)+3 种基金Research Climb Plan of ZJED(pd2013383)Opening Project of State Key Laboratory of High Performance Ceramics and Superfine Microstructure(SKL201409SIC)Xinmiao talent project of Zhejiang Province(2013R424060)College Students Research Project of Wenzhou University(14xk193)
文摘As BiVO4 is one of the most popular visible-light-responding photocatalysts, it has been widely used for visiblelight-driven water splitting and environmental purification. However, the typical photocatalytic activity of unmodified BiVO4 for the degradation of organic pollutants is still not impressive. To address this limitation, we studied Fe2O3-modified porous BiVO4 nanoplates. Compared with unmodified BiVO4, the Fe2O3-modified porous Bi VO4 nanoplates showed significantly enhanced photocatalytic activities in decomposing both dye and colorless pollutant models, such as rhodamine B(Rh B) and phenol,respectively. The pseudo-first-order reaction rate constants for the degradation of RhB and phenol on Fe2O3-modified BiVO4 porous nanoplates are 27 and 31 times larger than that of pristine Bi VO4, respectively. We also found that the Fe2O3 may act as an efficient non-precious metal co-catalyst, which is responsible for the excellent photocatalytic activity of Fe2O3/BiVO4.Graphical Abstract Fe2O3, as a cheap and efficient co-catalyst, could greatly enhance the photocatalytic activity of Bi VO4 porous nanoplates in decomposing organic pollutants.
