The surface/interfacial reactivity of clay is a critical factor influencing the sedimentation of coal slurry water.To achieve efficient sedimentation of coal slurry water,this paper introduces a novel approach that re...The surface/interfacial reactivity of clay is a critical factor influencing the sedimentation of coal slurry water.To achieve efficient sedimentation of coal slurry water,this paper introduces a novel approach that regulates the hydrophobicity of defective active sites in clay minerals.Fe^(3+)-doped kaolinite(Fe^(3+)-Kao)was synthesized by hydrothermal methods.Subsequently,tests were conducted on the adsorption capacity,surface wettability,and agglomeration sedimentation of alkyl amine/ammonium salts(AAS)on Fe^(3+)-Kao surfaces.Fe^(3+)doping significantly enhances AAS adsorption and alters surface properties from hydrophilic to hydrophobic,promoting kaolinite particle aggregation and sedimentation,thereby improving coal slurry water treatment efficiency.Molecular dynamics(MD)simulations were performed to analyze the statistical adsorption behavior of AAS on Fe^(3+)-Kao surfaces.The simulation results indicate that the mechanism by which Fe^(3+)doping influences the hydrophobic regulation of kaolinite surfaces is due to the enhanced interfacial interactions between the kaolinite surface and AAS,where the interfacial effects are more pronounced on surfaces closer to the dopant sites.The findings of this research offer valuable insights for future studies on other types of lattice defects in clay minerals,as well as for the development of more efficient treatment chemicals for coal slurry water.展开更多
Graphitic carbon nitride(g‐C_(3)N_(4))is a highly recognized two‐dimensional semiconductor material known for its exceptional chemical and physical stability,environmental friendliness,and pollution‐free advantages...Graphitic carbon nitride(g‐C_(3)N_(4))is a highly recognized two‐dimensional semiconductor material known for its exceptional chemical and physical stability,environmental friendliness,and pollution‐free advantages.These remarkable properties have sparked extensive research in the field of energy storage.This review paper presents the latest advances in the utilization of g‐C_(3)N_(4)in various energy storage technologies,including lithium‐ion batteries,lithium‐sulfur batteries,sodium‐ion batteries,potassium‐ion batteries,and supercapacitors.One of the key strengths of g‐C_(3)N_(4)lies in its simple preparation process along with the ease of optimizing its material structure.It possesses abundant amino and Lewis basic groups,as well as a high density of nitrogen,enabling efficient charge transfer and electrolyte solution penetration.Moreover,the graphite‐like layered structure and the presence of largeπbonds in g‐C_(3)N_(4)contribute to its versatility in preparing multifunctional materials with different dimensions,element and group doping,and conjugated systems.These characteristics open up possibilities for expanding its application in energy storage devices.This article comprehensively reviews the research progress on g‐C_(3)N_(4)in energy storage and highlights its potential for future applications in this field.By exploring the advantages and unique features of g‐C_(3)N_(4),this paper provides valuable insights into harnessing the full potential of this material for energy storage applications.展开更多
Ion beam-induced luminescence(IBIL) experiments were performed to investigate the in situ luminescence of GaN/Al_(2)O_(3) at varying ion energies,which allowed for the measurement of defects at different depths within...Ion beam-induced luminescence(IBIL) experiments were performed to investigate the in situ luminescence of GaN/Al_(2)O_(3) at varying ion energies,which allowed for the measurement of defects at different depths within the material.The energies of H^(+)were set to 500 keV,640 keV and 2 MeV,the Bragg peaks of which correspond to the GaN film,GaN/Al_(2)O_(3) heterojunction and Al_(2)O_(3) substrate,respectively.A photoluminescence measurement at 250 K was also performed for comparison,during which only near band edge(NBE) and yellow band luminescence in the GaN film were observed.The evolution of the luminescence of the NBE and yellow band in the GaN film was discussed,and both exhibited a decrease with the fluence of H^(+).Additionally,the luminescence of F centers,induced by oxygen vacancies,and Cr^(3+),resulting from the ^(2)E →^(4)A_(2) radiative transition in Al_(2)O_(3),were measured using 2 MeV H^(+).The luminescence intensity of F centers increases gradually with the fluence of H^(+).The luminescence evolution of Cr^(3+)is consistent with a yellow band center,attributed to its weak intensity,and it is situated within the emission band of the yellow band in the GaN film.Our results show that IBIL measurement can effectively detect the luminescence behavior of multilayer films by adjusting the ion energy.Luminescence measurement can be excited by various techniques,but IBIL can satisfy in situ luminescence measurement,and multilayer structural materials of tens of micrometers can be measured through IBIL by adjusting the energy of the inducing ions.The evolution of defects at different layers with ion fluence can be obtained.展开更多
The nanotitanium dioxide (TiO2) photocatalytic and porous ceramic filtering technique is one of the advanced methods to effectively treat organic wastewater. The TiO2 sol doped with Fe^3+ ions was prepared by sol-g...The nanotitanium dioxide (TiO2) photocatalytic and porous ceramic filtering technique is one of the advanced methods to effectively treat organic wastewater. The TiO2 sol doped with Fe^3+ ions was prepared by sol-gel processing. The influences of the process conditions of coating nanophotocatalytic material- Fe^3+-TiO2 film on the surface of porous ceramic filter by dipping-lift method on the performance of porous ceramic filter were studied. The porous ceramic filters have two functions at the same time, filtration and photocatalytic degradation. The results of this study showed that the pH and viscosity of the sol, amount of Fe^3+ ions doped as well as the coating times greatly affect the quality of coating film, the performance parameters and the photocatalytic activity of the porous ceramic filter. When the pH of the sol is 3-4, the viscosity is about 6 mPa.S, the amount of doped Fe^3+ ions is about 2.0 g/L, the porous ceramic filter has been shown to have the best filtering performance and photocatalytic activity. In this condition, the porosity of porous ceramic is about 42.5%, the pore diameter is 8-10μm. The degradation of methyl-orange is 74.76% under lighting for 120 rain.展开更多
In this study, nanosized TiO2 co-doped with Fe3+ and Nd3+ ions was synthesized via a sol-gel method. The metallic ion doped TiO2 was thoroughly characterized with XRD and UV-vis, and the photocatalytic activity was ev...In this study, nanosized TiO2 co-doped with Fe3+ and Nd3+ ions was synthesized via a sol-gel method. The metallic ion doped TiO2 was thoroughly characterized with XRD and UV-vis, and the photocatalytic activity was evaluated by degrading methylene blue (MB) solution. The results indicated that TiO2 crystalline size was reduced and phase transformation of anatase to rutile was suppressed as the content of doped Nd3+ ion increased in the co-doped TiO2. The UV-vis spectra of co-doped TiO2 seemed to simply overlay two spectra of single metal doped TiO2, and had significantly increased absorbance in the ranges of 400~500 nm, 565~600 nm and 730~765 nm as compared to pure TiO2. The photocatalytic activity of co-doped TiO2 was obviously enhanced, and raised about 30% compared to that of pure TiO2 as doped Nd3+ content was 0.15% and Fe3+ content was 0.05%, respectively. The enhanced catalytic activity was attributed to a synergistic effect of two doped ions, where doped Fe3+ ion inhibited the recombination of photogenerated electron and hole, and Nd3+ ion brought more surface carboxyl to promote the degradation reaction.展开更多
In this study, the adsorption kinetics, equilibrium and thermodynamics of Fe3+ ions on natural (NAP) and synthetic (HAP) apaties were examined. The adsorption efficiency of Fe3+ onto the NAP and HAP was increased with...In this study, the adsorption kinetics, equilibrium and thermodynamics of Fe3+ ions on natural (NAP) and synthetic (HAP) apaties were examined. The adsorption efficiency of Fe3+ onto the NAP and HAP was increased with increasing temperature. The kinetics of adsorption of Fe3+ ions was discussed using three kinetic models, the pseudo-first-order, the pseudo-second-order and the intra-particle diffusion model. The experimental data fitted very well the pseudo-second-order kinetic model. The initial sorption rate and the activation energy were also calculated. The activation energy of the sorption was calculated as 37.15 and 49.84 kJ·mol 1 for NAP and HAP, respectively. Experimental results were also analysed by the Langmuir, Freundlich and Dubinin–Redushkevich (D–R) isotherm equations at different temperatures. RL separation factor for Langmuir and the n value for Freundlich isotherm show that Fe3+ ions are favorably adsorbed by NAP and HAP. Various thermodynamic parameters such as enthalpy (ΔH), Gibbs free energy (ΔG) and entropy (ΔS) changes were computed and the results showed that the adsorption of Fe3+ ions onto NAP and HAP were spontaneous and endothermic in nature.展开更多
Sodium-ion batteries(SIBs)have rapidly risen to the forefront of energy storage systems as a promising supplementary for Lithium-ion batteries(LIBs).Na_(3)V_(2)(PO_(4))_(2)F_(3)(NVPF)as a common cathode of SIBs,featur...Sodium-ion batteries(SIBs)have rapidly risen to the forefront of energy storage systems as a promising supplementary for Lithium-ion batteries(LIBs).Na_(3)V_(2)(PO_(4))_(2)F_(3)(NVPF)as a common cathode of SIBs,features the merits of high operating voltage,small volume change and favorable specific energy density.However,it suffers from poor cycling stability and rate performance induced by its low intrinsic conductivity.Herein,we propose an ingenious strategy targeting superior SIBs through cross-linked NVPF with multi-dimensional nanocarbon frameworks composed of amorphous carbon and carbon nanotubes(NVPF@C@CNTs).This rational design ensures favorable particle size for shortened sodium ion transmission pathway as well as improved electronic transfer network,thus leading to enhanced charge transfer kinetics and superior cycling stability.Benefited from this unique structure,significantly improved electrochemical properties are obtained,including high specific capacity(126.9 mAh g^(-1)at 1 C,1 C=128 mA g^(-1))and remarkably improved long-term cycling stability with 93.9%capacity retention after 1000 cycles at 20 C.The energy density of 286.8 Wh kg^(-1)can be reached for full cells with hard carbon as anode(NVPF@C@CNTs//HC).Additionally,the electrochemical performance of the full cell at high temperature is also investigated(95.3 mAh g^(-1)after 100 cycles at 1 C at 50℃).Such nanoscale dual-carbon networks engineering and thorough discussion of ion diffusion kinetics might make contributions to accelerating the process of phosphate cathodes in SIBs for large-scale energy storages.展开更多
During the process of KDP crystal growth, metal ions strongly affect the growth habit and optical properties of KDP single crystal. In this paper, KDP crystals were grown from an aqueous solution doped with different ...During the process of KDP crystal growth, metal ions strongly affect the growth habit and optical properties of KDP single crystal. In this paper, KDP crystals were grown from an aqueous solution doped with different concentration of Fe^3+ dopant by traditional temperaturereduction method and "point-seed" rapid growth method. Furthermore, we examined the light scatter and measured the transmission of these KDP crystals. It is found that the dopant of Fe^3+ ion can improve the stability of the KDP growth solution when its concentration is less than 30 ppm. The effects of Fe^3+ ion on the growth habit and optical properties of KDP crystal are also obvious.展开更多
基金supported by the National key research and development Program of China(No.2023YFE0100600)the National Natural Science Foundation of China(Nos.52174233 and 52474282)the Natural Science Research Project of Anhui Educational Committee(No.2022AH030083)。
文摘The surface/interfacial reactivity of clay is a critical factor influencing the sedimentation of coal slurry water.To achieve efficient sedimentation of coal slurry water,this paper introduces a novel approach that regulates the hydrophobicity of defective active sites in clay minerals.Fe^(3+)-doped kaolinite(Fe^(3+)-Kao)was synthesized by hydrothermal methods.Subsequently,tests were conducted on the adsorption capacity,surface wettability,and agglomeration sedimentation of alkyl amine/ammonium salts(AAS)on Fe^(3+)-Kao surfaces.Fe^(3+)doping significantly enhances AAS adsorption and alters surface properties from hydrophilic to hydrophobic,promoting kaolinite particle aggregation and sedimentation,thereby improving coal slurry water treatment efficiency.Molecular dynamics(MD)simulations were performed to analyze the statistical adsorption behavior of AAS on Fe^(3+)-Kao surfaces.The simulation results indicate that the mechanism by which Fe^(3+)doping influences the hydrophobic regulation of kaolinite surfaces is due to the enhanced interfacial interactions between the kaolinite surface and AAS,where the interfacial effects are more pronounced on surfaces closer to the dopant sites.The findings of this research offer valuable insights for future studies on other types of lattice defects in clay minerals,as well as for the development of more efficient treatment chemicals for coal slurry water.
基金Science Development Foundation of Hubei University of Science&Technology,Grant/Award Numbers:2021F005,2021ZX14,2020TD01,2021ZX0Xianning City Program of Science&Technology,Grant/Award Number:2022ZRKX051Hubei University of Science and Technology Doctoral Research Initiation Project,Grant/Award Number:BK202217。
文摘Graphitic carbon nitride(g‐C_(3)N_(4))is a highly recognized two‐dimensional semiconductor material known for its exceptional chemical and physical stability,environmental friendliness,and pollution‐free advantages.These remarkable properties have sparked extensive research in the field of energy storage.This review paper presents the latest advances in the utilization of g‐C_(3)N_(4)in various energy storage technologies,including lithium‐ion batteries,lithium‐sulfur batteries,sodium‐ion batteries,potassium‐ion batteries,and supercapacitors.One of the key strengths of g‐C_(3)N_(4)lies in its simple preparation process along with the ease of optimizing its material structure.It possesses abundant amino and Lewis basic groups,as well as a high density of nitrogen,enabling efficient charge transfer and electrolyte solution penetration.Moreover,the graphite‐like layered structure and the presence of largeπbonds in g‐C_(3)N_(4)contribute to its versatility in preparing multifunctional materials with different dimensions,element and group doping,and conjugated systems.These characteristics open up possibilities for expanding its application in energy storage devices.This article comprehensively reviews the research progress on g‐C_(3)N_(4)in energy storage and highlights its potential for future applications in this field.By exploring the advantages and unique features of g‐C_(3)N_(4),this paper provides valuable insights into harnessing the full potential of this material for energy storage applications.
文摘Ion beam-induced luminescence(IBIL) experiments were performed to investigate the in situ luminescence of GaN/Al_(2)O_(3) at varying ion energies,which allowed for the measurement of defects at different depths within the material.The energies of H^(+)were set to 500 keV,640 keV and 2 MeV,the Bragg peaks of which correspond to the GaN film,GaN/Al_(2)O_(3) heterojunction and Al_(2)O_(3) substrate,respectively.A photoluminescence measurement at 250 K was also performed for comparison,during which only near band edge(NBE) and yellow band luminescence in the GaN film were observed.The evolution of the luminescence of the NBE and yellow band in the GaN film was discussed,and both exhibited a decrease with the fluence of H^(+).Additionally,the luminescence of F centers,induced by oxygen vacancies,and Cr^(3+),resulting from the ^(2)E →^(4)A_(2) radiative transition in Al_(2)O_(3),were measured using 2 MeV H^(+).The luminescence intensity of F centers increases gradually with the fluence of H^(+).The luminescence evolution of Cr^(3+)is consistent with a yellow band center,attributed to its weak intensity,and it is situated within the emission band of the yellow band in the GaN film.Our results show that IBIL measurement can effectively detect the luminescence behavior of multilayer films by adjusting the ion energy.Luminescence measurement can be excited by various techniques,but IBIL can satisfy in situ luminescence measurement,and multilayer structural materials of tens of micrometers can be measured through IBIL by adjusting the energy of the inducing ions.The evolution of defects at different layers with ion fluence can be obtained.
文摘The nanotitanium dioxide (TiO2) photocatalytic and porous ceramic filtering technique is one of the advanced methods to effectively treat organic wastewater. The TiO2 sol doped with Fe^3+ ions was prepared by sol-gel processing. The influences of the process conditions of coating nanophotocatalytic material- Fe^3+-TiO2 film on the surface of porous ceramic filter by dipping-lift method on the performance of porous ceramic filter were studied. The porous ceramic filters have two functions at the same time, filtration and photocatalytic degradation. The results of this study showed that the pH and viscosity of the sol, amount of Fe^3+ ions doped as well as the coating times greatly affect the quality of coating film, the performance parameters and the photocatalytic activity of the porous ceramic filter. When the pH of the sol is 3-4, the viscosity is about 6 mPa.S, the amount of doped Fe^3+ ions is about 2.0 g/L, the porous ceramic filter has been shown to have the best filtering performance and photocatalytic activity. In this condition, the porosity of porous ceramic is about 42.5%, the pore diameter is 8-10μm. The degradation of methyl-orange is 74.76% under lighting for 120 rain.
基金Project supported by Beijing Excellent Talents Training Fund (20061D0502200299)
文摘In this study, nanosized TiO2 co-doped with Fe3+ and Nd3+ ions was synthesized via a sol-gel method. The metallic ion doped TiO2 was thoroughly characterized with XRD and UV-vis, and the photocatalytic activity was evaluated by degrading methylene blue (MB) solution. The results indicated that TiO2 crystalline size was reduced and phase transformation of anatase to rutile was suppressed as the content of doped Nd3+ ion increased in the co-doped TiO2. The UV-vis spectra of co-doped TiO2 seemed to simply overlay two spectra of single metal doped TiO2, and had significantly increased absorbance in the ranges of 400~500 nm, 565~600 nm and 730~765 nm as compared to pure TiO2. The photocatalytic activity of co-doped TiO2 was obviously enhanced, and raised about 30% compared to that of pure TiO2 as doped Nd3+ content was 0.15% and Fe3+ content was 0.05%, respectively. The enhanced catalytic activity was attributed to a synergistic effect of two doped ions, where doped Fe3+ ion inhibited the recombination of photogenerated electron and hole, and Nd3+ ion brought more surface carboxyl to promote the degradation reaction.
文摘In this study, the adsorption kinetics, equilibrium and thermodynamics of Fe3+ ions on natural (NAP) and synthetic (HAP) apaties were examined. The adsorption efficiency of Fe3+ onto the NAP and HAP was increased with increasing temperature. The kinetics of adsorption of Fe3+ ions was discussed using three kinetic models, the pseudo-first-order, the pseudo-second-order and the intra-particle diffusion model. The experimental data fitted very well the pseudo-second-order kinetic model. The initial sorption rate and the activation energy were also calculated. The activation energy of the sorption was calculated as 37.15 and 49.84 kJ·mol 1 for NAP and HAP, respectively. Experimental results were also analysed by the Langmuir, Freundlich and Dubinin–Redushkevich (D–R) isotherm equations at different temperatures. RL separation factor for Langmuir and the n value for Freundlich isotherm show that Fe3+ ions are favorably adsorbed by NAP and HAP. Various thermodynamic parameters such as enthalpy (ΔH), Gibbs free energy (ΔG) and entropy (ΔS) changes were computed and the results showed that the adsorption of Fe3+ ions onto NAP and HAP were spontaneous and endothermic in nature.
基金financially supported by Science and Technology Foundation of Guizhou Province(QKHZC[2020]2Y037)the Science and Technology Innovation Program of Hunan Province(2020RC4005,2019RS1004)+2 种基金Research start-up funding from Central South University(202044019)Innovation Mover Program of Central South University(2020CX007)National Natural Science Foundation of China(U21A20284)
文摘Sodium-ion batteries(SIBs)have rapidly risen to the forefront of energy storage systems as a promising supplementary for Lithium-ion batteries(LIBs).Na_(3)V_(2)(PO_(4))_(2)F_(3)(NVPF)as a common cathode of SIBs,features the merits of high operating voltage,small volume change and favorable specific energy density.However,it suffers from poor cycling stability and rate performance induced by its low intrinsic conductivity.Herein,we propose an ingenious strategy targeting superior SIBs through cross-linked NVPF with multi-dimensional nanocarbon frameworks composed of amorphous carbon and carbon nanotubes(NVPF@C@CNTs).This rational design ensures favorable particle size for shortened sodium ion transmission pathway as well as improved electronic transfer network,thus leading to enhanced charge transfer kinetics and superior cycling stability.Benefited from this unique structure,significantly improved electrochemical properties are obtained,including high specific capacity(126.9 mAh g^(-1)at 1 C,1 C=128 mA g^(-1))and remarkably improved long-term cycling stability with 93.9%capacity retention after 1000 cycles at 20 C.The energy density of 286.8 Wh kg^(-1)can be reached for full cells with hard carbon as anode(NVPF@C@CNTs//HC).Additionally,the electrochemical performance of the full cell at high temperature is also investigated(95.3 mAh g^(-1)after 100 cycles at 1 C at 50℃).Such nanoscale dual-carbon networks engineering and thorough discussion of ion diffusion kinetics might make contributions to accelerating the process of phosphate cathodes in SIBs for large-scale energy storages.
基金the State High Technology Program for Inertial Confinement Fusion and National Science Foundation (No.59823003)Project of United Foundation (No.10676019)Youth Scientist Fund of Shandong Province (Nos. 2004BS04022 and 03BS079)
文摘During the process of KDP crystal growth, metal ions strongly affect the growth habit and optical properties of KDP single crystal. In this paper, KDP crystals were grown from an aqueous solution doped with different concentration of Fe^3+ dopant by traditional temperaturereduction method and "point-seed" rapid growth method. Furthermore, we examined the light scatter and measured the transmission of these KDP crystals. It is found that the dopant of Fe^3+ ion can improve the stability of the KDP growth solution when its concentration is less than 30 ppm. The effects of Fe^3+ ion on the growth habit and optical properties of KDP crystal are also obvious.