Co@Au core shell nanoparticles(NPs) of different shell thicknesses were fabricated by a combination of the displacement process and the reduction-deposition process in a microfluidic reactor. The effect of the shell t...Co@Au core shell nanoparticles(NPs) of different shell thicknesses were fabricated by a combination of the displacement process and the reduction-deposition process in a microfluidic reactor. The effect of the shell thickness on the fine structures(local atom arrangement) of core materials was investigated by X-ray Absorption Near Edge Structure(XANES) and Extended X-ray Absorption Fine Structure(EXAFS).The results indicate that the shell thickness affects the fine structure of the core materials by causing atomic re-arrangement between the hexagonal close pack(hcp) and the face centered cubic(fcc) structure, and forming Co-Au bonds in the core-shell interface.展开更多
The properties of Raman phonons are very important due to the fact that they can availably reflect some important physical information. An abnormal Raman peak is observed at about 558 cm-1 in In film composed of In/In...The properties of Raman phonons are very important due to the fact that they can availably reflect some important physical information. An abnormal Raman peak is observed at about 558 cm-1 in In film composed of In/InOx core-shell structured nanoparticles, and the phonon mode stays very stable when the temperature changes. Our results indicate that this Raman scattering is attributed to the existence of incomplete indium oxide in the oxide shell.展开更多
Hierarchical magnetic-dielectric composites are promising functional materials with prospective applications in microwave absorption(MA)field.Herein,a three-dimension hierarchical“nanotubes on microrods,”core–shell...Hierarchical magnetic-dielectric composites are promising functional materials with prospective applications in microwave absorption(MA)field.Herein,a three-dimension hierarchical“nanotubes on microrods,”core–shell magnetic metal–carbon composite is rationally constructed for the first time via a fast metal–organic frameworksbased ligand exchange strategy followed by a carbonization treatment with melamine.Abundant magnetic CoFe nanoparticles are embedded within one-dimensional graphitized carbon/carbon nanotubes supported on micro-scale Mo2N rod(Mo2N@CoFe@C/CNT),constructing a special multi-dimension hierarchical MA material.Ligand exchange reaction is found to determine the formation of hierarchical magnetic-dielectric composite,which is assembled by dielectric Mo2N as core and spatially dispersed CoFe nanoparticles within C/CNTs as shell.Mo2N@CoFe@C/CNT composites exhibit superior MA performance with maximum reflection loss of−53.5 dB at 2 mm thickness and show a broad effective absorption bandwidth of 5.0 GHz.The Mo2N@CoFe@C/CNT composites hold the following advantages:(1)hierarchical core–shell structure offers plentiful of heterojunction interfaces and triggers interfacial polarization,(2)unique electronic migration/hop paths in the graphitized C/CNTs and Mo2N rod facilitate conductive loss,(3)highly dispersed magnetic CoFe nanoparticles within“tubes on rods”matrix build multi-scale magnetic coupling network and reinforce magnetic response capability,confirmed by the off-axis electron holography.展开更多
As a promising alternative anode material,silicon(Si)presents a larger capacity than the commercial anode to achieve large capacity lithium-ion batteries.However,the application of pure Si as anode is hampered by limi...As a promising alternative anode material,silicon(Si)presents a larger capacity than the commercial anode to achieve large capacity lithium-ion batteries.However,the application of pure Si as anode is hampered by limitations such as volume expansion,low conductivity and unstable solid electrolyte interphase.To break through these limitations,the core-shell Si@Li4Ti5O12nanocomposite,which was prepared via in-situ self-assembly reaction and decompressive boiling fast concentration method,was proposed in this work.This anode combines the advantages of nano-sized Si particle and pure Li4Ti5O12(LTO)coating layer,improving the performance of the lithium-ion batteries.The Si@Li4Ti5O12 anode displays a high initial discharge/charge specific capacity of 1756/1383 m Ahg^-1 at 500 mAg^-1(representing high initial coulombic efficiency of 78.8%),a large rate capability(specific capacity of 620 mAhg^-1 at4000 mAg^-1),an outstanding cycling stability(reversible specific capacity of 883 mAhg^-1 after 150 cycles)and a low volume expansion rate(only 3.3% after 150 cycles).Moreover,the synthesis process shows the merits of efficiency,simplicity,and economy,providing a reliable method to fabricate large capacity Si@Li4Ti5O12nanocomposite anode materials for practical lithium-ion batteries.展开更多
The sintering-alloying processes of nickel(Ni),iron(Fe),and magnesium(Mg) with aluminum(Al) nanoparticles were studied by molecular dynamics simulation with the analytic embedded-atom model(AEAM) potential.Potential e...The sintering-alloying processes of nickel(Ni),iron(Fe),and magnesium(Mg) with aluminum(Al) nanoparticles were studied by molecular dynamics simulation with the analytic embedded-atom model(AEAM) potential.Potential energy,mean heterogeneous coordination number NAB,and surface atomic number Nsurf-A were used to monitor the sintering-reaction processes.The effects of surface segregation,heat of formation,and melting point on the sinteringalloying processes were discussed.Results revealed that sintering proceeded in two stages.First,atoms with low surface energy diffused onto the surface of atoms with high surface energy;second,metal atoms diffused with one another with increased system temperature to a threshold value.Under the same initial conditions,the sintering reaction rate of the three systems increased in the order MgAl <FeAl <NiAl.Depending on the initial reaction temperature,the final core-shell(FeAl and MgAl) and alloyed(NiAl and FeAl) nanoconfigurations can be observed.展开更多
The microstructures and magnetic properties of nanoparticles, each composed of an antiferromagnetic （AFM） manganese-oxide shell and a ferromagnetic-like core of manganese-gallium （MnGa） compounds, are studied. The...The microstructures and magnetic properties of nanoparticles, each composed of an antiferromagnetic （AFM） manganese-oxide shell and a ferromagnetic-like core of manganese-gallium （MnGa） compounds, are studied. The coreshell structure is confirmed by transmission electron microscope （TEM）. The ferromagnetic-like core contains three kinds of MnGa binary compounds, i.e., ferrimagnetic （FI） DO22-type MnaGa, ferromagnetic （FM） Mn8Gas, and AFM DO19-type Mn3Ga, of which the first two correspond respectively to a hard magnetic phase and to a soft one. Decoupling effect between these two phases is found at low temperature, which weakens gradually with increasing temperature and disappears above 200 K. The exchange bias （EB） effect is observed simultaneously, which is caused by the exchange coupling between the AFM shell and FM-like core. A large coercivity of 6.96 kOe （1Oe = 79.5775 A·m^-1） and a maximum EB value of 0.45 kOe are achieved at 300 K and 200 K respectively.展开更多
MXene is a new type of layered two-dimensional transition metal carbide materials differing from graphene, demonstrating intriguing chemical/physical properties. Here the chemical modification of MXene and next fabric...MXene is a new type of layered two-dimensional transition metal carbide materials differing from graphene, demonstrating intriguing chemical/physical properties. Here the chemical modification of MXene and next fabrication of core-shell MXene-COOH@(PEI/PAA)_n composites have been investigated. The obtained MXene-based composites were treated with gold nanoparticles to form MXene—COOH@(PEI/PAA)_n@AuNPs nanocomposites, and their catalytic properties for nitro-compounds were studied. The prepared nanocomposites demonstrated good catalytic activity and reproducibility, showing potential applications in composite catalysts and environmental fields.展开更多
Lanthanide-sensitized upconverting nanoparticles(UCNPs)are widely studied because of their unusual optical characteristics,such as large antenna-generated anti-Stokes shifts,high photostability,and narrow emission ban...Lanthanide-sensitized upconverting nanoparticles(UCNPs)are widely studied because of their unusual optical characteristics,such as large antenna-generated anti-Stokes shifts,high photostability,and narrow emission bandwidths,which can be harnessed for a variety of applications including bioimaging,sensing,information security and high-level anticounterfeiting.The diverse requirements of these applications typically require precise control over upconversion luminescence(UCL).Recently,the concept of energy migration upconversion has emerged as an effective approach to modulate UCL for various lanthanide ions.Moreover,it provides valuable insights into the fundamental comprehension of energy transfer mechanisms on the nanoscale,thereby contributing to the design of efficient lanthanide-sensitized UCNPs and their practical applications.Here we present a comprehensive overview of the latest developments in energy migration upconversion in lanthanide-sensitized nanoparticles for photon upconversion tuning,encompassing design strategies,mechanistic investigations and applications.Additionally,some future prospects in the field of energy migration upconversion are also discussed.展开更多
The effects of metal core dimension, oxide shell thickness and ellipsoid aspect ratio of Al-Al2O3 core-shell nanoparticles on the near-infrared and visible absorption spectra of nanocomposite Al-Al2O3/nitrocellulose...The effects of metal core dimension, oxide shell thickness and ellipsoid aspect ratio of Al-Al2O3 core-shell nanoparticles on the near-infrared and visible absorption spectra of nanocomposite Al-Al2O3/nitrocellulose（NC） film are investigated by numerical calculations. Both the size-dependent interband transitions and frequency-dependent free electron damping of the nanometallic aluminium are taken into account in the calculations. Oxidation effect of nanoaluminium is also analysed. It is shown that oxidation may enhance but may also reduce the optical absorption, depending on the excited light energy and initial dimension of nanoparticle. Metal core size and excited light energy dominate the absorption characteristic. The absorption ability of ellipsoidal nanoparticles is larger than that of spheroidal nanoparticles and increases by the square index as the aspect ratio increases. These calculations will provide some significant theoretical guidance for the preparation and laser ignition of nanoenergetic materials.展开更多
Developing high-performance and low-cost electrocatalysts is key to achieve the clean-energy target.Herein,a dual regulation method is proposed to prepare a 3D honeycomb-like carbon-based catalyst with stable Fe/Co co...Developing high-performance and low-cost electrocatalysts is key to achieve the clean-energy target.Herein,a dual regulation method is proposed to prepare a 3D honeycomb-like carbon-based catalyst with stable Fe/Co co-dopants.Fe atoms are highly dispersed and fixed to the polymer microsphere,followed by a high-temperature decomposition,for the generation of carbon-based catalyst with a honeycomb-like structure.The as-prepared catalyst contains a large number of Fe/Co nanoparticles(Fe/Co NPs),providing the excellent catalytic activity and durability in oxygen reduction reaction,oxygen evolution reaction and hydrogen evolution reaction.The Zn-air battery assembled by the as-prepared catalyst as air cathode shows a good charge and discharge capacity,and it exhibits an ultra-long service life by maintaining a stable charge and discharge platform for a 311-h cycle.Further X-ray absorption fine structure characterization and density functional theory calculation confirms that the Fe doping optimizes the intermediate adsorption process and electron transfer of Co.展开更多
Experimental work has been focused on the formation of alloyed Au-Cu nanoparticles under simultaneous laser exposure and mechanical stirring of mixed monometallic colloids, here referred to as dual procedure. As a fee...Experimental work has been focused on the formation of alloyed Au-Cu nanoparticles under simultaneous laser exposure and mechanical stirring of mixed monometallic colloids, here referred to as dual procedure. As a feed for the dual procedure, Au and Cu monometallic nanoparticle colloids have been using a laser ablation technique. To accomplish this, bulk targets were ablated with 1064 nm wavelength Nd: YAG laser in a pure acetone(99.99%) environment. Ultraviolet-visible optical absorption spectrometry, transmission electron microscopy, X-ray diffraction and X-ray fluorescence technique have been used to characterize the nanoparticles. It has been found that experimental conditions such as stirring and laser parameters strongly affect the synthesized particle properties, including the size, shape, composition and stability of the nanoparticles. Alloy nanoparticles containing 39% Au – 61% Cu have also been prepared in the same process, but in two forms of a homogeneous alloy and a core-shell structure.展开更多
A facile step-by-step approach is developed for synthesizing the high-efficiency and magnetic recyclable Fe3O4@SiO2@Ag@Ni trepang-like nanocomposites.This method involves coating Fe2O3 nanorods with a uniform silica l...A facile step-by-step approach is developed for synthesizing the high-efficiency and magnetic recyclable Fe3O4@SiO2@Ag@Ni trepang-like nanocomposites.This method involves coating Fe2O3 nanorods with a uniform silica layer,reduction in 10%H2/Ar atmosphere to transform the Fe2O3 into magnetic Fe3O4,and finally depositing Ag@Ni core-shell nanoparticles on the L-lysine modified surface of Fe3O4@SiO2 nanorods.The fabricated nanocomposites are further characterized by x-ray diffraction,transmission electron microscopy,scanning electron microscope,Fourier transform infrared spectroscopy,and inductively coupled plasma mass spectroscopy.The Fe3O4@SiO2@Ag@Ni trepang-like nanocomposites exhibit remarkably higher catalytic efficiency than monometallic Fe3O4@SiO2@Ag nanocomposites toward the degradation of Rhodamine B（RhB） at room temperature,and maintain superior catalytic activity even after six cycles.In addition,these samples could be easily separated from the catalytic system by an external magnet and reused,which shows great potential applications in treating waste water.展开更多
基金support from National Science Foundation of China(NSFC,Grant No.50971010)the Fundamental Research Funds for the Central Universities(YWF-11-03-Q-002)
文摘Co@Au core shell nanoparticles(NPs) of different shell thicknesses were fabricated by a combination of the displacement process and the reduction-deposition process in a microfluidic reactor. The effect of the shell thickness on the fine structures(local atom arrangement) of core materials was investigated by X-ray Absorption Near Edge Structure(XANES) and Extended X-ray Absorption Fine Structure(EXAFS).The results indicate that the shell thickness affects the fine structure of the core materials by causing atomic re-arrangement between the hexagonal close pack(hcp) and the face centered cubic(fcc) structure, and forming Co-Au bonds in the core-shell interface.
基金Project supported by the National Natural Science Foundation of China （Grant Nos. 11374069 and 61006078）, the National Basic Research Program of China （Grant Nos. 2010CB934102 and 2010CB934101）, and the ＂Strategic Priority Research Program＂ of the Chinese Academy of Sciences （Grant No. XDA09020300）.
文摘The properties of Raman phonons are very important due to the fact that they can availably reflect some important physical information. An abnormal Raman peak is observed at about 558 cm-1 in In film composed of In/InOx core-shell structured nanoparticles, and the phonon mode stays very stable when the temperature changes. Our results indicate that this Raman scattering is attributed to the existence of incomplete indium oxide in the oxide shell.
基金This work was supported by the Ministry of Science and Technology of China(973 Project No.2018YFA0209102)the National Natural Science Foundation of China(11727807,51725101,51672050,61790581).
文摘Hierarchical magnetic-dielectric composites are promising functional materials with prospective applications in microwave absorption(MA)field.Herein,a three-dimension hierarchical“nanotubes on microrods,”core–shell magnetic metal–carbon composite is rationally constructed for the first time via a fast metal–organic frameworksbased ligand exchange strategy followed by a carbonization treatment with melamine.Abundant magnetic CoFe nanoparticles are embedded within one-dimensional graphitized carbon/carbon nanotubes supported on micro-scale Mo2N rod(Mo2N@CoFe@C/CNT),constructing a special multi-dimension hierarchical MA material.Ligand exchange reaction is found to determine the formation of hierarchical magnetic-dielectric composite,which is assembled by dielectric Mo2N as core and spatially dispersed CoFe nanoparticles within C/CNTs as shell.Mo2N@CoFe@C/CNT composites exhibit superior MA performance with maximum reflection loss of−53.5 dB at 2 mm thickness and show a broad effective absorption bandwidth of 5.0 GHz.The Mo2N@CoFe@C/CNT composites hold the following advantages:(1)hierarchical core–shell structure offers plentiful of heterojunction interfaces and triggers interfacial polarization,(2)unique electronic migration/hop paths in the graphitized C/CNTs and Mo2N rod facilitate conductive loss,(3)highly dispersed magnetic CoFe nanoparticles within“tubes on rods”matrix build multi-scale magnetic coupling network and reinforce magnetic response capability,confirmed by the off-axis electron holography.
基金the financial support from the National Natural Science Foundation of China (51876052, 51676128)
文摘As a promising alternative anode material,silicon(Si)presents a larger capacity than the commercial anode to achieve large capacity lithium-ion batteries.However,the application of pure Si as anode is hampered by limitations such as volume expansion,low conductivity and unstable solid electrolyte interphase.To break through these limitations,the core-shell Si@Li4Ti5O12nanocomposite,which was prepared via in-situ self-assembly reaction and decompressive boiling fast concentration method,was proposed in this work.This anode combines the advantages of nano-sized Si particle and pure Li4Ti5O12(LTO)coating layer,improving the performance of the lithium-ion batteries.The Si@Li4Ti5O12 anode displays a high initial discharge/charge specific capacity of 1756/1383 m Ahg^-1 at 500 mAg^-1(representing high initial coulombic efficiency of 78.8%),a large rate capability(specific capacity of 620 mAhg^-1 at4000 mAg^-1),an outstanding cycling stability(reversible specific capacity of 883 mAhg^-1 after 150 cycles)and a low volume expansion rate(only 3.3% after 150 cycles).Moreover,the synthesis process shows the merits of efficiency,simplicity,and economy,providing a reliable method to fabricate large capacity Si@Li4Ti5O12nanocomposite anode materials for practical lithium-ion batteries.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11572124 and 51871096)the Natural Science Foundation of Hunan Province of China(Grant Nos.2018JJ4044 and 2018JJ3100).
文摘The sintering-alloying processes of nickel(Ni),iron(Fe),and magnesium(Mg) with aluminum(Al) nanoparticles were studied by molecular dynamics simulation with the analytic embedded-atom model(AEAM) potential.Potential energy,mean heterogeneous coordination number NAB,and surface atomic number Nsurf-A were used to monitor the sintering-reaction processes.The effects of surface segregation,heat of formation,and melting point on the sinteringalloying processes were discussed.Results revealed that sintering proceeded in two stages.First,atoms with low surface energy diffused onto the surface of atoms with high surface energy;second,metal atoms diffused with one another with increased system temperature to a threshold value.Under the same initial conditions,the sintering reaction rate of the three systems increased in the order MgAl <FeAl <NiAl.Depending on the initial reaction temperature,the final core-shell(FeAl and MgAl) and alloyed(NiAl and FeAl) nanoconfigurations can be observed.
基金Projected supported by the National Basic Research Program of China(Grant No.2010CB934603)the National High Technology Research and Development Program of China(863 Program)(Grant No.2011AA03A402)the National Natural Science Foundation of China(Grant Nos.50931006,51271177,and 51271179)
文摘The microstructures and magnetic properties of nanoparticles, each composed of an antiferromagnetic （AFM） manganese-oxide shell and a ferromagnetic-like core of manganese-gallium （MnGa） compounds, are studied. The coreshell structure is confirmed by transmission electron microscope （TEM）. The ferromagnetic-like core contains three kinds of MnGa binary compounds, i.e., ferrimagnetic （FI） DO22-type MnaGa, ferromagnetic （FM） Mn8Gas, and AFM DO19-type Mn3Ga, of which the first two correspond respectively to a hard magnetic phase and to a soft one. Decoupling effect between these two phases is found at low temperature, which weakens gradually with increasing temperature and disappears above 200 K. The exchange bias （EB） effect is observed simultaneously, which is caused by the exchange coupling between the AFM shell and FM-like core. A large coercivity of 6.96 kOe （1Oe = 79.5775 A·m^-1） and a maximum EB value of 0.45 kOe are achieved at 300 K and 200 K respectively.
基金financially supported by the National Natural Science Foundation of China (Nos.21473153 and 51771162)Support Program for the Top Young Talents of Hebei Province,China Postdoctoral Science Foundation (No.2015M580214)+1 种基金the Scientific and Technological Research and Development Program of Qinhuangdao City (No.201701B004)Undergraduate Training Programs for Innovation and Entrepreneurship of Yanshan University (No.CXXL2017227)
文摘MXene is a new type of layered two-dimensional transition metal carbide materials differing from graphene, demonstrating intriguing chemical/physical properties. Here the chemical modification of MXene and next fabrication of core-shell MXene-COOH@(PEI/PAA)_n composites have been investigated. The obtained MXene-based composites were treated with gold nanoparticles to form MXene—COOH@(PEI/PAA)_n@AuNPs nanocomposites, and their catalytic properties for nitro-compounds were studied. The prepared nanocomposites demonstrated good catalytic activity and reproducibility, showing potential applications in composite catalysts and environmental fields.
基金supported by Senior Talent Fund of Jiangsu University(No.5501310021)China Postdoctoral Science Foundation(No.2023M741419)+1 种基金the Young Elite Scientist Sponsorship Program by ZJAST(No.G301310002)Research Fund for International Scientists(No.22350710187).
文摘Lanthanide-sensitized upconverting nanoparticles(UCNPs)are widely studied because of their unusual optical characteristics,such as large antenna-generated anti-Stokes shifts,high photostability,and narrow emission bandwidths,which can be harnessed for a variety of applications including bioimaging,sensing,information security and high-level anticounterfeiting.The diverse requirements of these applications typically require precise control over upconversion luminescence(UCL).Recently,the concept of energy migration upconversion has emerged as an effective approach to modulate UCL for various lanthanide ions.Moreover,it provides valuable insights into the fundamental comprehension of energy transfer mechanisms on the nanoscale,thereby contributing to the design of efficient lanthanide-sensitized UCNPs and their practical applications.Here we present a comprehensive overview of the latest developments in energy migration upconversion in lanthanide-sensitized nanoparticles for photon upconversion tuning,encompassing design strategies,mechanistic investigations and applications.Additionally,some future prospects in the field of energy migration upconversion are also discussed.
基金supported by the National Natural Science Foundation of China (Grant No 20573028)
文摘The effects of metal core dimension, oxide shell thickness and ellipsoid aspect ratio of Al-Al2O3 core-shell nanoparticles on the near-infrared and visible absorption spectra of nanocomposite Al-Al2O3/nitrocellulose（NC） film are investigated by numerical calculations. Both the size-dependent interband transitions and frequency-dependent free electron damping of the nanometallic aluminium are taken into account in the calculations. Oxidation effect of nanoaluminium is also analysed. It is shown that oxidation may enhance but may also reduce the optical absorption, depending on the excited light energy and initial dimension of nanoparticle. Metal core size and excited light energy dominate the absorption characteristic. The absorption ability of ellipsoidal nanoparticles is larger than that of spheroidal nanoparticles and increases by the square index as the aspect ratio increases. These calculations will provide some significant theoretical guidance for the preparation and laser ignition of nanoenergetic materials.
基金supported by the National Natural Science Foundation of China(No.51973009)supported by open foundation of Guangxi Key Laboratory of Processing for Non-ferrous Metals and Featured Materials,Guangxi University(No.2022GXYSOF21).
文摘Developing high-performance and low-cost electrocatalysts is key to achieve the clean-energy target.Herein,a dual regulation method is proposed to prepare a 3D honeycomb-like carbon-based catalyst with stable Fe/Co co-dopants.Fe atoms are highly dispersed and fixed to the polymer microsphere,followed by a high-temperature decomposition,for the generation of carbon-based catalyst with a honeycomb-like structure.The as-prepared catalyst contains a large number of Fe/Co nanoparticles(Fe/Co NPs),providing the excellent catalytic activity and durability in oxygen reduction reaction,oxygen evolution reaction and hydrogen evolution reaction.The Zn-air battery assembled by the as-prepared catalyst as air cathode shows a good charge and discharge capacity,and it exhibits an ultra-long service life by maintaining a stable charge and discharge platform for a 311-h cycle.Further X-ray absorption fine structure characterization and density functional theory calculation confirms that the Fe doping optimizes the intermediate adsorption process and electron transfer of Co.
基金supported by the Materials and Energy Research Center (MERC),Nanotechnology and Advanced Materials Department in the framework of Project Number 728811
文摘Experimental work has been focused on the formation of alloyed Au-Cu nanoparticles under simultaneous laser exposure and mechanical stirring of mixed monometallic colloids, here referred to as dual procedure. As a feed for the dual procedure, Au and Cu monometallic nanoparticle colloids have been using a laser ablation technique. To accomplish this, bulk targets were ablated with 1064 nm wavelength Nd: YAG laser in a pure acetone(99.99%) environment. Ultraviolet-visible optical absorption spectrometry, transmission electron microscopy, X-ray diffraction and X-ray fluorescence technique have been used to characterize the nanoparticles. It has been found that experimental conditions such as stirring and laser parameters strongly affect the synthesized particle properties, including the size, shape, composition and stability of the nanoparticles. Alloy nanoparticles containing 39% Au – 61% Cu have also been prepared in the same process, but in two forms of a homogeneous alloy and a core-shell structure.
基金supported by the National Basic Research Program of China(Grant No.2015CB921502)the National Natural Science Foundation of China(Grant Nos.11474184 and 11174183)+1 种基金the 111 Project(Grant No.B13029)the Fundamental Research Funds of Shandong University,China
文摘A facile step-by-step approach is developed for synthesizing the high-efficiency and magnetic recyclable Fe3O4@SiO2@Ag@Ni trepang-like nanocomposites.This method involves coating Fe2O3 nanorods with a uniform silica layer,reduction in 10%H2/Ar atmosphere to transform the Fe2O3 into magnetic Fe3O4,and finally depositing Ag@Ni core-shell nanoparticles on the L-lysine modified surface of Fe3O4@SiO2 nanorods.The fabricated nanocomposites are further characterized by x-ray diffraction,transmission electron microscopy,scanning electron microscope,Fourier transform infrared spectroscopy,and inductively coupled plasma mass spectroscopy.The Fe3O4@SiO2@Ag@Ni trepang-like nanocomposites exhibit remarkably higher catalytic efficiency than monometallic Fe3O4@SiO2@Ag nanocomposites toward the degradation of Rhodamine B（RhB） at room temperature,and maintain superior catalytic activity even after six cycles.In addition,these samples could be easily separated from the catalytic system by an external magnet and reused,which shows great potential applications in treating waste water.
