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
NASICON-type Na_(3)V_(2)(PO_(4))_(3)(NVP)materials are seen as highly promising cathode materials in the field of sodium-ion batteries due to their low cost,a solid three-dimensional skeleton and good theoretical capa...NASICON-type Na_(3)V_(2)(PO_(4))_(3)(NVP)materials are seen as highly promising cathode materials in the field of sodium-ion batteries due to their low cost,a solid three-dimensional skeleton and good theoretical capacity,as well as high ionic conductivity.Nevertheless,the problem of low intrinsic electronic conductivity and energy density has limited the practical application of the materials.To address this issue,the relevant research team has successfully achieved remarkable research results through unremitting exploration and practical innovation.In this work,the crystal structure,ion migration mechanism and sodium storage mechanism of NVP cathode materials are systematically reviewed,with a focus on summarizing the latest progress of V-site doping modification research,classifying and exploring V-site doping from the perspectives of electronic structure,lattice strain and entropy,and briefly describing the optimization mechanism of V-site doping on electrochemical performance.In addition,the challenges and prospects for the future development of NVP cathode materials are presented,which are believed to provide new thinking for the design and development of high-performance NVP cathode materials and contribute to the large-scale application of sodium-ion batteries.展开更多
The limited redox capability of photocatalysts often leads to harmful NO_(2) byproduct formation during photocatalytic NO oxidation.Herein,Bi_(4)Ti_(3)O_(12) nanosheets modified with plasmonic metallic bismuth and abu...The limited redox capability of photocatalysts often leads to harmful NO_(2) byproduct formation during photocatalytic NO oxidation.Herein,Bi_(4)Ti_(3)O_(12) nanosheets modified with plasmonic metallic bismuth and abundant oxygen vacancies were synthesized via an in-situ reduction method.The optimized catalyst(BTOR2,with a molar ratio of 40%NaBH_(4) to Bi_(4)Ti_(3)O_(12))achieved a maximum NO removal efficiency of 62.3%,significantly higher than pristine Bi_(4)Ti_(3)O_(12)(40.5%) while minimizing NO_(2) production.The results reveal that the synergistic effects of Bi’s plasmonic resonance and oxygen vacancies enhanced visible light absorption and charge separation.The density functional theory(DFT)analysis showed electrons can transfer from Bi_(4)Ti_(3)O_(12)to Bi,promoting O_(2)activation to·O_(2)^(-)radicals.In-situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS)confirmed that light-induced H2O adsorption was strengthened,improving·OH radical generation.These radicals promoted the selective conversion of activated NO-to NO_(3)^(-),rather than NO_(2).This work provides valuable insights for advancing research into efficient photocatalysts for air pollution control.展开更多
Transparent glass-ceramics containing MgSiO_(3)and/or Mg_(2)SiO_(4)nanocrystals were prepared.Effects of MgO/SiO_(2)ratio on crystallization properties of MgSiO_(3)and Mg_(2)SiO_(4)nanocrystals were investigated.When ...Transparent glass-ceramics containing MgSiO_(3)and/or Mg_(2)SiO_(4)nanocrystals were prepared.Effects of MgO/SiO_(2)ratio on crystallization properties of MgSiO_(3)and Mg_(2)SiO_(4)nanocrystals were investigated.When the MgO/SiO_(2)ratio is relatively low,crystallization of MgSiO_(3)is favored,whereas a higher MgO/SiO_(2)ratio tends to promote the crystallization of Mg_(2)SiO_(4).Glass-ceramics are transparent in the visible range due to the small size of the precipitated nanocrystals.Replacing SiO_(2)with MgO results in an increase in Vickers hardness,and the Vickers hardness can be further enhanced through the precipitation of MgSiO_(3)and Mg_(2)SiO_(4)nanocrystals.The findings presented herein are meaningful for the preparation of highly transparent glass-ceramics containing MgSiO_(3)and Mg_(2)SiO_(4)nanocrystals.展开更多
The escalating pace of industrialization has significantly intensified water pollution challenges,for instance,the persistent organic pollutants like methyl orange(MO).Conventional remediation techniques,such as adsor...The escalating pace of industrialization has significantly intensified water pollution challenges,for instance,the persistent organic pollutants like methyl orange(MO).Conventional remediation techniques,such as adsorption and biological degradation,are often hampered by low efficiency and the risk of secondary pollution.Photocatalysis emerges as a promising sustainable alternative;however,the benchmark material titanium dioxide(TiO_(2))suffers from its intrinsic limitations,notably its wide bandgap energy(≥3.4 eV)restricting its activity to the region of the ultraviolet light and its rapid recombination of photogenerated charge carriers.To overcome these constraints,this research focused on synthesizing novel TiO_(2)/Sn_(3)O_(4) heterojunction composite photocatalysts via a solvothermal approach.Comprehensive characterization techniques confirmed the successful formation of the composite,which revealed that ultrathin Sn3O4 nanosheets uniformly coated TiO_(2) nanospheres.This unique architecture effectively reduced the overall crystallinity and introduced the beneficial oxygen vacancies.Under visible-light irradiation(λ≥420 nm),the optimized TiO_(2)/Sn3O4 composite exhibited the exceptional photocatalytic performance,which achieved 96%degradation of MO within just 60 minutes.The calculated apparent kinetic rate constant(0.103 min^(-1))was remarkably(5.15 times)higher than that of pristine TiO_(2).ESR experiments identified that hydroxyl radicals(·OH)was the predominant active species driving the degradation.Furthermore,cyclic degradation tests demonstrated its excellent material stability,with the composite retaining 85%of its initial efficiency after four consecutive reuse cycles.This work underscored the synergistic effects within the TiO_(2)/Sn_(3)O_(4) heterojunction,which significantly enhanced the visible-light absorption,charge separation,and photocatalytic activity,which provided the valuable insights for designing efficient,stable catalysts for the advanced environmental remediation applications.展开更多
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.52574348)the Natural Science Foundation of Hebei Province(no.B2024501004)+2 种基金the Fundamental Research Funds for the Central Universities(no.N2423013)the Shijiazhuang Basic Research Project(no.241790667A)the Performance Subsidy Fund for Key Laboratory of Dielectric and Electrolyte Functional Material Hebei Province(no.22567627H).
文摘NASICON-type Na_(3)V_(2)(PO_(4))_(3)(NVP)materials are seen as highly promising cathode materials in the field of sodium-ion batteries due to their low cost,a solid three-dimensional skeleton and good theoretical capacity,as well as high ionic conductivity.Nevertheless,the problem of low intrinsic electronic conductivity and energy density has limited the practical application of the materials.To address this issue,the relevant research team has successfully achieved remarkable research results through unremitting exploration and practical innovation.In this work,the crystal structure,ion migration mechanism and sodium storage mechanism of NVP cathode materials are systematically reviewed,with a focus on summarizing the latest progress of V-site doping modification research,classifying and exploring V-site doping from the perspectives of electronic structure,lattice strain and entropy,and briefly describing the optimization mechanism of V-site doping on electrochemical performance.In addition,the challenges and prospects for the future development of NVP cathode materials are presented,which are believed to provide new thinking for the design and development of high-performance NVP cathode materials and contribute to the large-scale application of sodium-ion batteries.
基金supported by the Natural Science Foundation of Chongqing(Nos.CSTB2024NSCQ-MSX1278,CSTB2023NSCQ-MSX0006)Technology Innovation Project of Shapingba District,Chongqing(No.2024004)+2 种基金Science and Technology Research Program of Chongqing Municipal Education Commission(Nos.KJZD-K202403102,KJQN202103110,KJQN202400512,KJQN202403107)National Natural Science Foundation of China(No.22406014)China Postdoctoral Science Foundation(No.2023MD744137).
文摘The limited redox capability of photocatalysts often leads to harmful NO_(2) byproduct formation during photocatalytic NO oxidation.Herein,Bi_(4)Ti_(3)O_(12) nanosheets modified with plasmonic metallic bismuth and abundant oxygen vacancies were synthesized via an in-situ reduction method.The optimized catalyst(BTOR2,with a molar ratio of 40%NaBH_(4) to Bi_(4)Ti_(3)O_(12))achieved a maximum NO removal efficiency of 62.3%,significantly higher than pristine Bi_(4)Ti_(3)O_(12)(40.5%) while minimizing NO_(2) production.The results reveal that the synergistic effects of Bi’s plasmonic resonance and oxygen vacancies enhanced visible light absorption and charge separation.The density functional theory(DFT)analysis showed electrons can transfer from Bi_(4)Ti_(3)O_(12)to Bi,promoting O_(2)activation to·O_(2)^(-)radicals.In-situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS)confirmed that light-induced H2O adsorption was strengthened,improving·OH radical generation.These radicals promoted the selective conversion of activated NO-to NO_(3)^(-),rather than NO_(2).This work provides valuable insights for advancing research into efficient photocatalysts for air pollution control.
基金Funded by the National Natural Science Foundation of China(Nos.52202026,and 62175192)the Natural Science Foundation of Hubei Province(No.2022CFB762)。
文摘Transparent glass-ceramics containing MgSiO_(3)and/or Mg_(2)SiO_(4)nanocrystals were prepared.Effects of MgO/SiO_(2)ratio on crystallization properties of MgSiO_(3)and Mg_(2)SiO_(4)nanocrystals were investigated.When the MgO/SiO_(2)ratio is relatively low,crystallization of MgSiO_(3)is favored,whereas a higher MgO/SiO_(2)ratio tends to promote the crystallization of Mg_(2)SiO_(4).Glass-ceramics are transparent in the visible range due to the small size of the precipitated nanocrystals.Replacing SiO_(2)with MgO results in an increase in Vickers hardness,and the Vickers hardness can be further enhanced through the precipitation of MgSiO_(3)and Mg_(2)SiO_(4)nanocrystals.The findings presented herein are meaningful for the preparation of highly transparent glass-ceramics containing MgSiO_(3)and Mg_(2)SiO_(4)nanocrystals.
文摘The escalating pace of industrialization has significantly intensified water pollution challenges,for instance,the persistent organic pollutants like methyl orange(MO).Conventional remediation techniques,such as adsorption and biological degradation,are often hampered by low efficiency and the risk of secondary pollution.Photocatalysis emerges as a promising sustainable alternative;however,the benchmark material titanium dioxide(TiO_(2))suffers from its intrinsic limitations,notably its wide bandgap energy(≥3.4 eV)restricting its activity to the region of the ultraviolet light and its rapid recombination of photogenerated charge carriers.To overcome these constraints,this research focused on synthesizing novel TiO_(2)/Sn_(3)O_(4) heterojunction composite photocatalysts via a solvothermal approach.Comprehensive characterization techniques confirmed the successful formation of the composite,which revealed that ultrathin Sn3O4 nanosheets uniformly coated TiO_(2) nanospheres.This unique architecture effectively reduced the overall crystallinity and introduced the beneficial oxygen vacancies.Under visible-light irradiation(λ≥420 nm),the optimized TiO_(2)/Sn3O4 composite exhibited the exceptional photocatalytic performance,which achieved 96%degradation of MO within just 60 minutes.The calculated apparent kinetic rate constant(0.103 min^(-1))was remarkably(5.15 times)higher than that of pristine TiO_(2).ESR experiments identified that hydroxyl radicals(·OH)was the predominant active species driving the degradation.Furthermore,cyclic degradation tests demonstrated its excellent material stability,with the composite retaining 85%of its initial efficiency after four consecutive reuse cycles.This work underscored the synergistic effects within the TiO_(2)/Sn_(3)O_(4) heterojunction,which significantly enhanced the visible-light absorption,charge separation,and photocatalytic activity,which provided the valuable insights for designing efficient,stable catalysts for the advanced environmental remediation applications.
