Microwave-induced substitutional combustion reaction was utilized to fabricate porous ceramic composite from Fe_3O_4/Al powder mixtures.The porous composite body was obtained by controlling the combustion reaction pro...Microwave-induced substitutional combustion reaction was utilized to fabricate porous ceramic composite from Fe_3O_4/Al powder mixtures.The porous composite body was obtained by controlling the combustion reaction progress in a 2.45 GHz single mode applicator.Prior to the fabrication of the porous body,heating behavior of the powder mixtures were studied in the separated electric(E)and magnetic(H)fields.In addition,heating ability of the microwave fabricated porous product was also investigated.Fe_3O_4 powder can be heated up easily in both maximum H and E field, but a better heating was observed in the maximum H field.Regardless of the mixtures ratio(mixing compositions), maximum H field shows better heating characteristics.In E-field heating,temperature of the Fe_3O_4 samples decreased sharply when Al powder was added.However,the same phenomenon was not observed in the maximum H field heating. Thus,fabrication of the porous composite body was carrying out in maximum H field.Through an adequate control of the reaction progress,products with a porous structure consisting of well-distributed metal particles in the alumina and/or hercynite matrix were obtained.Consequently,heating of the fabricated porous composite body was also been successfully carried out in the maximum H field.Product phases and microstructure were the main factors influencing the heating ability of the porous composite body.展开更多
In this work,we report a fabrication of recyclable iron oxide decorated MoS_(2)nanosheets via a facile liq-uid exfoliation approach and solvothermal reaction for visible-light photodegradation of tetracycline.The prep...In this work,we report a fabrication of recyclable iron oxide decorated MoS_(2)nanosheets via a facile liq-uid exfoliation approach and solvothermal reaction for visible-light photodegradation of tetracycline.The prepared Fe_(3)O_(4)-MoS_(2)was characterized by X-ray diffraction,transmission electron microscopy,X-ray photoelectron spectros-copy,Raman spectroscopy,magnetic hysteresis,and nitrogen adsorption-desorption isotherms.Experimental results indicate that,successful attachment of Fe_(3)O_(4)nanoparticles to MoS_(2)sheets has been achieved.The enhanced surface area of Fe_(3)O_(4)-MoS_(2)induced high rates of adsorption and the adsorbed tetracycline was degraded to 90%after 150 min of visible exposure,which is better than that from pure MoS_(2).The introduction of Fe_(3)O_(4)not only enhances the photo-catalytic performance of Fe_(3)O_(4)-MoS_(2),but also enables its convenient recovery from water by an external magnetic field.Furthermore,both the photocatalytic activity and composite phase of Fe_(3)O_(4)-MoS_(2)were well-retained over cy-cles.Owing to its efficient photocatalytic activity,good stability and magnetic recyclability,the Fe_(3)O_(4)-MoS_(2)nano-composite is considered to be a promising photocatalyst for wastewater treatment.展开更多
With growing concerns regarding electromagnetic pollution,low-cost,environmentally friendly,and high-performance electromagnetic wave absorption(EWA)materials have attracted significant attention.This paper reports on...With growing concerns regarding electromagnetic pollution,low-cost,environmentally friendly,and high-performance electromagnetic wave absorption(EWA)materials have attracted significant attention.This paper reports on the synthesis of porous Fe_(3)O_(4)/C composites that incorporate dielectric and magnetic loss mechanisms via the carbothermal reduction method and optimization of waste ratio to enhance EWA performance.The Fe_(3)O_(4)/C composites with 10wt%soybean residues(Fe_(3)O_(4)/C-10),demonstrated the best EWA performance,achieving the minimum reflection loss of−56.4 dB and a bandwidth of 2.14 GHz at a thickness of 2.23 mm.This enhanced EWA performance is primarily attributable to improved impedance matching and the synergistic effect between dielectric and magnetic losses.Furthermore,radar cross-sectional simulations confirmed the practical feasibility of the porous Fe_(3)O_(4)/C composites.This study proposes a viable strategy for utilizing soybean residue and electrolytic manganese residue,highlighting their potential applications in EWA.展开更多
Herein,a novel Janus-structured multifunctional membrane with integrated electromagnetic interference(EMI)shielding and personalized thermal management is fabricated using shear-induced in situ fibrillation and vacuum...Herein,a novel Janus-structured multifunctional membrane with integrated electromagnetic interference(EMI)shielding and personalized thermal management is fabricated using shear-induced in situ fibrillation and vacuum-assisted filtration.Interestingly,within the polytetrafluoroethylene(PTFE)-carbon nanotube(CNT)-Fe_(3)O_(4)layer(FCFe),CNT nanofibers interweave with PTFE fibers to form a stable“silk-like”structure that effectively captures Fe_(3)O_(4)particles.By incorporating a highly conductive MXene layer,the FCFe/MXene(FCFe/M)membrane exhibits excellent electrical/thermal conductivity,mechanical properties,and flame retardancy.Impressively,benefiting from the rational regulation of component proportions and the design of a Janus structure,the FCFe/M membrane with a thickness of only 84.9μm delivers outstanding EMI shielding effectiveness of 44.56 dB in the X-band,with a normalized specific SE reaching 10,421.3 dB cm^(2)g^(-1),which is attributed to the“absorption-reflection-reabsorption”mechanism.Furthermore,the membrane demonstrates low-voltage-driven Joule heating and fast-response photothermal performance.Under the stimulation of a 3 V voltage and an optical power density of 320 mW cm^(-2),the surface temperatures of the FCFe/M membranes can reach up to 140.4 and 145.7℃,respectively.In brief,the FCFe/M membrane with anti-electromagnetic radiation and temperature regulation is an attractive candidate for the next generation of wearable electronics,EMI compatibility,visual heating,thermotherapy,and military and aerospace applications.展开更多
The Fenton method is an effective technology for the removal of organic materials from wastewater.In this work,an induced catalyst Fe_(3)O_(4) was synthesized by a hydrothermal method,and the modulation of the chemica...The Fenton method is an effective technology for the removal of organic materials from wastewater.In this work,an induced catalyst Fe_(3)O_(4) was synthesized by a hydrothermal method,and the modulation of the chemical composition of Fe_(3)O_(4) crystals was achieved under the microwave shock method with the same effect as that of calcination treatment.Fe_(3)O_(4) catalyst for the removal of the dye Rhodamine B (Rh B) from polluted wastewater under microwave (MW),H_(2)O_(2) system.The results showed that Fe_(3)O_(4) nanomicrospheres prepared by microwave shock exhibited superior catalytic activity under the conditions of 500 W,0.4 mol/L H_(2)O_(2) and10 mg/L Rh B,and the removal rate of Rh B reached 98.5%after 10 min.The Fe_(3)O_(4) catalysts also exhibited good stability and degradation efficiency.Electron paramagnetic resonance experiments confirmed that·OH plays a major role in the rapid degradation of Rh B.Under microwave action,the catalyst produces electron-hole pairs,in which the holes react with OH-produced by water ionisation to form·OH,and the microwave-treated Fe_(3)O_(4) produces more active species.Fe^(3+)and Fe^(2+)serve as microwave catalytic activity centers and Fenton catalytic activity centers,respectively.This research demonstrates that optimizing the Fe^(2+)/Fe^(3+) ratio significantly enhances the degradation efficiency of Rh B.This study presents novel views regarding the mechanism of microwave synergistic catalyst-induced Fenton.展开更多
The pollution especially organic dyes pollution of water resources is an urgent issue to be solved.It is crucial to develop highly efficient,low cost and recyclable heterogeneous catalysts for wastewater treatment.In ...The pollution especially organic dyes pollution of water resources is an urgent issue to be solved.It is crucial to develop highly efficient,low cost and recyclable heterogeneous catalysts for wastewater treatment.In this study,a heterogeneous Fenton catalyst loaded with Fe_(3)O_(4)nanoparticles was prepared by one step pyrolysis using natural crop waste corncob as carbon source.The prepared porous carbon catalyst can effectively degrade methyl orange(MO,25 mg·L^(-1))at room temperature,and the degradation rate is 99.7%.In addition to high catalytic degradation activity,the layered porous carbon structure of the catalyst also provides high stability and reusability.The degradation rate can be maintained above 93%after 10 cycles.Furthermore,the prepared catalyst is magnetic,which makes the catalyst easy to recycle in practical applications.In addition,the prepared Fe3O4/RCC catalyst has efficient Fenton degradation activity for bisphenol A(BPA)(96.9%)and antibiotic tetracycline hydrochloride(TC-HCl)(95.5%),which proves that it has universal applicability for the degradation of most organic pollutants.This study provides a feasible and scalable strategy to prepare a heterogeneous Fenton catalyst treating wastewater and high-value utilization of biomass waste.展开更多
In this work,for the first time,it is demonstrated that during the insertion/extraction of Na ions,the structural evolution at the Na_(4)site at a voltage range of 3-4 V is a key factor for the capacity decay of Na_(4...In this work,for the first time,it is demonstrated that during the insertion/extraction of Na ions,the structural evolution at the Na_(4)site at a voltage range of 3-4 V is a key factor for the capacity decay of Na_(4)Fe_(3)(PO_(4))_(2)P_(2)O_(7)(NFPP).Herein,a strategy of introducing columnar potassium ions at the Na_(4)site is proposed to address the aforementioned challenge.As a cathode material for sodium-ion batteries,the K_(0.12)Na_(3.88)Fe_(3)(PO_(4))_(2)P_(2)O_(7)/C(K-NFPP)composite enhances the reversibility of Na_(4)extraction.Specifically,the K-NFPP exhibits an initial discharge capacity of 107.8 mAh g^(-1)at a high current density of 5 C,with a capacity retention of 91.4% after 2000 cycles,outperforming the pristine NFPP material(81.1 m Ah g^(-1)and 67.1%).At 5 C,the K-NFPP also retains 81.5% of the reversible capacity at 0.1 C,whereas the NFPP only retains 68.3%.Moreover,the K-NFPP-based full-cell delivers an initial capacity of 110.1 m Ah g^(-1)at 1 C,with a capacity retention of 90% after 100 cycles.It is found that in comparison to K-doping of the Na1,Na2,and Na3 sites,K-doping at the Na4 site effectively optimizes the band gap and stabilizes the crystal structure,thereby reducing lattice changes of FeO_(6)evolution during Na^(+)insertion/extraction.As a result,the introduction of columnar potassium ions significantly enhances the capacity contribution of the Na_(4)site,optimizes reaction kinetics,and effectively mitigates the capacity decay of NFPP cathodes.It is believed that this study offers a new entry point for the application of NFPP in high-voltage sodium storage.展开更多
Mixed polyanion phosphate Na_(4)Fe_(3)(PO_(4))_(2)P_(2)O_(7)(NFPP)is regarded as the most promising cathode material for sodium-ion batteries(SIBs),due to its high structural stability and low-cost environmental frien...Mixed polyanion phosphate Na_(4)Fe_(3)(PO_(4))_(2)P_(2)O_(7)(NFPP)is regarded as the most promising cathode material for sodium-ion batteries(SIBs),due to its high structural stability and low-cost environmental friendliness.However,its intrinsic low conductivity and sluggish Na^(+)diffusion restricted the fast-charge and low-temperature sodium storage.Herein,an NFPP composite encapsulated by in-situ pyrolytic carbon and coupled with expanded graphite(NFPP@C/EG)was constructed via a sol-gel method followed by a ballmill procedure.Due to the dual-carbon modified strategy,this NFPP@C/EG only enhanced the electronic conductivity,but also endowed more channels for Na^(+)diffusion.As cathode for SIBs,the optimized NFPP(M-NFPP@C/EG)delivers excellent rate capability(capacity of~80.5 mAh/g at 50 C)and outstanding cycling stability(11000 cycles at 50 C with capacity retention of 89.85%).Additionally,cyclic voltammetry(CV)confirmed that its sodium storage behavior is pseudocapacitance-controlled,with in-situ electrochemical impedance spectroscopy(EIS)further elucidating improvements in electrode reaction kinetics.At lower temperatures(0℃),M-NFPP@C/EG demonstrated exceptional cycling performance(8800 cycles at 10 C with capacity retention of 95.81%).Moreover,pouch cells also exhibited excellent stability.This research demonstrates the feasibility of a dual carbon modification strategy in enhancing NFPP and proposes a low-cost,high-rate,and ultra-stable cathode material for SIBs.展开更多
文摘Microwave-induced substitutional combustion reaction was utilized to fabricate porous ceramic composite from Fe_3O_4/Al powder mixtures.The porous composite body was obtained by controlling the combustion reaction progress in a 2.45 GHz single mode applicator.Prior to the fabrication of the porous body,heating behavior of the powder mixtures were studied in the separated electric(E)and magnetic(H)fields.In addition,heating ability of the microwave fabricated porous product was also investigated.Fe_3O_4 powder can be heated up easily in both maximum H and E field, but a better heating was observed in the maximum H field.Regardless of the mixtures ratio(mixing compositions), maximum H field shows better heating characteristics.In E-field heating,temperature of the Fe_3O_4 samples decreased sharply when Al powder was added.However,the same phenomenon was not observed in the maximum H field heating. Thus,fabrication of the porous composite body was carrying out in maximum H field.Through an adequate control of the reaction progress,products with a porous structure consisting of well-distributed metal particles in the alumina and/or hercynite matrix were obtained.Consequently,heating of the fabricated porous composite body was also been successfully carried out in the maximum H field.Product phases and microstructure were the main factors influencing the heating ability of the porous composite body.
文摘In this work,we report a fabrication of recyclable iron oxide decorated MoS_(2)nanosheets via a facile liq-uid exfoliation approach and solvothermal reaction for visible-light photodegradation of tetracycline.The prepared Fe_(3)O_(4)-MoS_(2)was characterized by X-ray diffraction,transmission electron microscopy,X-ray photoelectron spectros-copy,Raman spectroscopy,magnetic hysteresis,and nitrogen adsorption-desorption isotherms.Experimental results indicate that,successful attachment of Fe_(3)O_(4)nanoparticles to MoS_(2)sheets has been achieved.The enhanced surface area of Fe_(3)O_(4)-MoS_(2)induced high rates of adsorption and the adsorbed tetracycline was degraded to 90%after 150 min of visible exposure,which is better than that from pure MoS_(2).The introduction of Fe_(3)O_(4)not only enhances the photo-catalytic performance of Fe_(3)O_(4)-MoS_(2),but also enables its convenient recovery from water by an external magnetic field.Furthermore,both the photocatalytic activity and composite phase of Fe_(3)O_(4)-MoS_(2)were well-retained over cy-cles.Owing to its efficient photocatalytic activity,good stability and magnetic recyclability,the Fe_(3)O_(4)-MoS_(2)nano-composite is considered to be a promising photocatalyst for wastewater treatment.
基金supported by the National Natural Science Foundation of China(No.52471221)the Natural Science Foundation of Hunan Province,China(No.2024JJ7145)the National Sustainable Development Agenda Innovation Demonstration Zone Hunan special project,China(No.2022sfq09).
文摘With growing concerns regarding electromagnetic pollution,low-cost,environmentally friendly,and high-performance electromagnetic wave absorption(EWA)materials have attracted significant attention.This paper reports on the synthesis of porous Fe_(3)O_(4)/C composites that incorporate dielectric and magnetic loss mechanisms via the carbothermal reduction method and optimization of waste ratio to enhance EWA performance.The Fe_(3)O_(4)/C composites with 10wt%soybean residues(Fe_(3)O_(4)/C-10),demonstrated the best EWA performance,achieving the minimum reflection loss of−56.4 dB and a bandwidth of 2.14 GHz at a thickness of 2.23 mm.This enhanced EWA performance is primarily attributable to improved impedance matching and the synergistic effect between dielectric and magnetic losses.Furthermore,radar cross-sectional simulations confirmed the practical feasibility of the porous Fe_(3)O_(4)/C composites.This study proposes a viable strategy for utilizing soybean residue and electrolytic manganese residue,highlighting their potential applications in EWA.
基金support from the National Natural Science Foundation of China(NSFC,Grant No.52175341)Shandong Provincial Natural Science Foundation(Grant No.ZR2022JQ24)Funding Project of Jinan City’s New Twenty Items for Colleges and Universities(Grant No.202333038).
文摘Herein,a novel Janus-structured multifunctional membrane with integrated electromagnetic interference(EMI)shielding and personalized thermal management is fabricated using shear-induced in situ fibrillation and vacuum-assisted filtration.Interestingly,within the polytetrafluoroethylene(PTFE)-carbon nanotube(CNT)-Fe_(3)O_(4)layer(FCFe),CNT nanofibers interweave with PTFE fibers to form a stable“silk-like”structure that effectively captures Fe_(3)O_(4)particles.By incorporating a highly conductive MXene layer,the FCFe/MXene(FCFe/M)membrane exhibits excellent electrical/thermal conductivity,mechanical properties,and flame retardancy.Impressively,benefiting from the rational regulation of component proportions and the design of a Janus structure,the FCFe/M membrane with a thickness of only 84.9μm delivers outstanding EMI shielding effectiveness of 44.56 dB in the X-band,with a normalized specific SE reaching 10,421.3 dB cm^(2)g^(-1),which is attributed to the“absorption-reflection-reabsorption”mechanism.Furthermore,the membrane demonstrates low-voltage-driven Joule heating and fast-response photothermal performance.Under the stimulation of a 3 V voltage and an optical power density of 320 mW cm^(-2),the surface temperatures of the FCFe/M membranes can reach up to 140.4 and 145.7℃,respectively.In brief,the FCFe/M membrane with anti-electromagnetic radiation and temperature regulation is an attractive candidate for the next generation of wearable electronics,EMI compatibility,visual heating,thermotherapy,and military and aerospace applications.
基金supported by Beijing Natural Science Foundation(No.2232062)the Fundamental Research Funds for the Central Universities (No.2652022006)。
文摘The Fenton method is an effective technology for the removal of organic materials from wastewater.In this work,an induced catalyst Fe_(3)O_(4) was synthesized by a hydrothermal method,and the modulation of the chemical composition of Fe_(3)O_(4) crystals was achieved under the microwave shock method with the same effect as that of calcination treatment.Fe_(3)O_(4) catalyst for the removal of the dye Rhodamine B (Rh B) from polluted wastewater under microwave (MW),H_(2)O_(2) system.The results showed that Fe_(3)O_(4) nanomicrospheres prepared by microwave shock exhibited superior catalytic activity under the conditions of 500 W,0.4 mol/L H_(2)O_(2) and10 mg/L Rh B,and the removal rate of Rh B reached 98.5%after 10 min.The Fe_(3)O_(4) catalysts also exhibited good stability and degradation efficiency.Electron paramagnetic resonance experiments confirmed that·OH plays a major role in the rapid degradation of Rh B.Under microwave action,the catalyst produces electron-hole pairs,in which the holes react with OH-produced by water ionisation to form·OH,and the microwave-treated Fe_(3)O_(4) produces more active species.Fe^(3+)and Fe^(2+)serve as microwave catalytic activity centers and Fenton catalytic activity centers,respectively.This research demonstrates that optimizing the Fe^(2+)/Fe^(3+) ratio significantly enhances the degradation efficiency of Rh B.This study presents novel views regarding the mechanism of microwave synergistic catalyst-induced Fenton.
基金supported by the National Natural Science Foundation of China(51572124)Natural Science Foundation of China Jiangsu Province(BK20230940)+2 种基金the Fundamental Research Funds for the Central Universities(30920130121001)a project funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD,China)a project funded by Jiangsu Funding Program for Excellent Postdoctoral Talent.
文摘The pollution especially organic dyes pollution of water resources is an urgent issue to be solved.It is crucial to develop highly efficient,low cost and recyclable heterogeneous catalysts for wastewater treatment.In this study,a heterogeneous Fenton catalyst loaded with Fe_(3)O_(4)nanoparticles was prepared by one step pyrolysis using natural crop waste corncob as carbon source.The prepared porous carbon catalyst can effectively degrade methyl orange(MO,25 mg·L^(-1))at room temperature,and the degradation rate is 99.7%.In addition to high catalytic degradation activity,the layered porous carbon structure of the catalyst also provides high stability and reusability.The degradation rate can be maintained above 93%after 10 cycles.Furthermore,the prepared catalyst is magnetic,which makes the catalyst easy to recycle in practical applications.In addition,the prepared Fe3O4/RCC catalyst has efficient Fenton degradation activity for bisphenol A(BPA)(96.9%)and antibiotic tetracycline hydrochloride(TC-HCl)(95.5%),which proves that it has universal applicability for the degradation of most organic pollutants.This study provides a feasible and scalable strategy to prepare a heterogeneous Fenton catalyst treating wastewater and high-value utilization of biomass waste.
基金financial support from the National Natural Science Foundation of China(52272237,22279101 and 22172117)the Natural Science Foundation of Shaanxi(2020JC-41 and 2024JC-YBQN-0141)+2 种基金the Scientific Research Program Funded by the Education Department of Shaanxi Provincial Government(22JP056)the S&T Program of Energy Shaanxi Laboratory(ESLB202402)the Foshan Science and Technology Innovation Team Project(1920001004098)。
文摘In this work,for the first time,it is demonstrated that during the insertion/extraction of Na ions,the structural evolution at the Na_(4)site at a voltage range of 3-4 V is a key factor for the capacity decay of Na_(4)Fe_(3)(PO_(4))_(2)P_(2)O_(7)(NFPP).Herein,a strategy of introducing columnar potassium ions at the Na_(4)site is proposed to address the aforementioned challenge.As a cathode material for sodium-ion batteries,the K_(0.12)Na_(3.88)Fe_(3)(PO_(4))_(2)P_(2)O_(7)/C(K-NFPP)composite enhances the reversibility of Na_(4)extraction.Specifically,the K-NFPP exhibits an initial discharge capacity of 107.8 mAh g^(-1)at a high current density of 5 C,with a capacity retention of 91.4% after 2000 cycles,outperforming the pristine NFPP material(81.1 m Ah g^(-1)and 67.1%).At 5 C,the K-NFPP also retains 81.5% of the reversible capacity at 0.1 C,whereas the NFPP only retains 68.3%.Moreover,the K-NFPP-based full-cell delivers an initial capacity of 110.1 m Ah g^(-1)at 1 C,with a capacity retention of 90% after 100 cycles.It is found that in comparison to K-doping of the Na1,Na2,and Na3 sites,K-doping at the Na4 site effectively optimizes the band gap and stabilizes the crystal structure,thereby reducing lattice changes of FeO_(6)evolution during Na^(+)insertion/extraction.As a result,the introduction of columnar potassium ions significantly enhances the capacity contribution of the Na_(4)site,optimizes reaction kinetics,and effectively mitigates the capacity decay of NFPP cathodes.It is believed that this study offers a new entry point for the application of NFPP in high-voltage sodium storage.
基金supported by the National Key Research and Development Program of China(No.2022YFB2502000)the National Natural Science Foundation of China(Nos.U21A20332,51771076,U21A200970,52301266)the Science and Technology Planning Project of Guangzhou(No.2024A04J3332)。
文摘Mixed polyanion phosphate Na_(4)Fe_(3)(PO_(4))_(2)P_(2)O_(7)(NFPP)is regarded as the most promising cathode material for sodium-ion batteries(SIBs),due to its high structural stability and low-cost environmental friendliness.However,its intrinsic low conductivity and sluggish Na^(+)diffusion restricted the fast-charge and low-temperature sodium storage.Herein,an NFPP composite encapsulated by in-situ pyrolytic carbon and coupled with expanded graphite(NFPP@C/EG)was constructed via a sol-gel method followed by a ballmill procedure.Due to the dual-carbon modified strategy,this NFPP@C/EG only enhanced the electronic conductivity,but also endowed more channels for Na^(+)diffusion.As cathode for SIBs,the optimized NFPP(M-NFPP@C/EG)delivers excellent rate capability(capacity of~80.5 mAh/g at 50 C)and outstanding cycling stability(11000 cycles at 50 C with capacity retention of 89.85%).Additionally,cyclic voltammetry(CV)confirmed that its sodium storage behavior is pseudocapacitance-controlled,with in-situ electrochemical impedance spectroscopy(EIS)further elucidating improvements in electrode reaction kinetics.At lower temperatures(0℃),M-NFPP@C/EG demonstrated exceptional cycling performance(8800 cycles at 10 C with capacity retention of 95.81%).Moreover,pouch cells also exhibited excellent stability.This research demonstrates the feasibility of a dual carbon modification strategy in enhancing NFPP and proposes a low-cost,high-rate,and ultra-stable cathode material for SIBs.
