The efficiency of nanoscale nonlinear elements in photonic integrated circuits is hindered by the physical limits to the nonlinear optical response of dielectrics,which cannot be engineered as it is a fundamental mate...The efficiency of nanoscale nonlinear elements in photonic integrated circuits is hindered by the physical limits to the nonlinear optical response of dielectrics,which cannot be engineered as it is a fundamental material property.Here,we experimentally demonstrate that ultrafast optical nonlinearities in doped semiconductors can be engineered and can easily exceed those of conventional undoped dielectrics.The electron response of heavily doped semiconductors acquires in fact a hydrodynamic character that introduces nonlocal effects as well as additional nonlinear sources.Our experimental findings are supported by a comprehensive computational analysis based on the hydrodynamic model.In particular,by studying third-harmonic generation from plasmonic nanoantenna arrays made out of heavily n-doped InGaAs with increasing levels of free-carrier density,we discriminate between hydrodynamic and dielectric nonlinearities.Most importantly,we demonstrate that the maximum nonlinear efficiency as well as its spectral location can be engineered by tuning the doping level.Crucially,the maximum efficiency can be increased by almost two orders of magnitude with respect to the classical dielectric nonlinearity.Having employed the common material platform InGaAs/InP that supports integrated waveguides,our findings pave the way for future exploitation of plasmonic nonlinearities in all-semiconductor photonic integrated circuits.展开更多
Semiconductor nanostructures have gained importance due to their potential application in future nano- electronic devices. For such applications, it is extremely important to understand the electrical properties of se...Semiconductor nanostructures have gained importance due to their potential application in future nano- electronic devices. For such applications, it is extremely important to understand the electrical properties of semi- conductor nanostructures. This review presents an overview of techniques to measure the electrical properties of individual and clusters of semiconductor nanostructures using microcopy based techniques or by fabricating metal- lic electrical contacts using lithography. Then it is shown that current-voltage （I-V） characteristics can be used to determine the conduction mechanism in these nanostructures. It has been explained that various material paramet- ers can be extracted from I-V characteristics. The frequently observed conduction mechanism in these nanostruc- tures such as thermally activated conduction, space charge limited current （SCLC）, hopping conduction, Poole Frenkel conduction, Schottky emission and Fowler Nordheim （FN） tunneling are explained in detail.展开更多
As the scaling down of semiconductor devices, it would be necessary to discover the structure-property relationship of semiconductor nanomaterials at nanometer scale. In this review, the quantitative characterization ...As the scaling down of semiconductor devices, it would be necessary to discover the structure-property relationship of semiconductor nanomaterials at nanometer scale. In this review, the quantitative characterization technique off-axis electron holography is introduced in details, followed by its applications in various semiconductor nanomaterials including group IV, compound and two-dimensional semiconductor nanostructures in static states as well as under various stimuli. The advantages and disadvantages of off-axis electron holography in material analysis are discussed, the challenges facing in-situ electron holographic study of semiconductor devices at working conditions are presented, and all the possible influencing factors need to be considered to achieve the final goal of fulfilling quantitative characterization of the structure-property relationship of semiconductor devices at their working conditions.展开更多
GaN nanorods are fabricated using inductively coupled plasma etching with Ni nano-island masks. The poly [2- methoxy-5-（2-ethyl）hexoxy-l,4-phenylenevinylene] （MEH-PPV）/GaN-nanorod hybrid structure is fabricated by...GaN nanorods are fabricated using inductively coupled plasma etching with Ni nano-island masks. The poly [2- methoxy-5-（2-ethyl）hexoxy-l,4-phenylenevinylene] （MEH-PPV）/GaN-nanorod hybrid structure is fabricated by depositing the MEH-PPV film on the GaN nanorods by using the spin-coating process. In the hybrid structure, the spatial separation is minimized to achieve high-emciency non-radiative resonant energy transfer. Optical properties of a novel device consisting of MEH-PPV/GaN-nanorod hybrid structure is studied by analyzing photoluminescenee （PL） spectra. Compared with the pure GaN nanorods, the PL intensity of the band edge emission of GaN in the MEH-PPV/GaN-nanorods is enhanced as much as three times, and the intensity of the yellow band is suppressed slightly. The obtained results are analyzed by energy transfer between the GaN nanorods and the MEH-PPV. An energy transfer model is proposed to explain the phenomenon.展开更多
ZnO tetrapods were synthesized by a typical thermal vapor-solid deposition method in a horizontal tube furnace.Structural characterization was carried out by transmission electron microscopy （TEM） and select-area el...ZnO tetrapods were synthesized by a typical thermal vapor-solid deposition method in a horizontal tube furnace.Structural characterization was carried out by transmission electron microscopy （TEM） and select-area electron diffraction （SAED）,which shows the presence of zinc blende nucleus in the center of tetrapods while the four branches taking hexagonal wurtzite structure.The electrical transport property of ZnO tetrapods was investigated through an in-situ nanoprobe system.The three branches of a tetrapod serve as source,drain,and ＂gate＂,respectively;while the fourth branch pointing upward works as the force trigger by vertically applying external force downward.The conductivity of each branch of ZnO-tetrapods increases 3-4 times under pressure.In such situation,the electrical current through the branches of ZnO tetrapods can be tuned by external force,and therefore a simple force sensor based on ZnO tetrapods has been demonstrated for the first time.展开更多
In this paper we analyze a long standing problem of the appearance of spurious,non-physical solutions arising in the application of the effective mass theory to low dimensional nanostructures.The theory results in a s...In this paper we analyze a long standing problem of the appearance of spurious,non-physical solutions arising in the application of the effective mass theory to low dimensional nanostructures.The theory results in a system of coupled eigenvalue PDEs that is usually supplemented by interface boundary conditions that can be derived from a variational formulation of the problem.We analyze such a system for the envelope functions and show that a failure to restrict their Fourier expansion coeffi-cients to small k components would lead to the appearance of non-physical solutions.We survey the existing methodologies to eliminate this difficulty and propose a simple and effective solution.This solution is demonstrated on an example of a two-band model for both bulk materials and low-dimensional nanostructures.Finally,based on the above requirement of small k,we derive a model for nanostructures with cylindrical symmetry and apply the developed model to the analysis of quantum dots using an eight-band model.展开更多
As the proportion of interfaces increases rapidly in nanomaterials,properties and quality of interfaces hugely impact the performance of advanced semiconductors.Here,the effect of interfaces is explored by comparative...As the proportion of interfaces increases rapidly in nanomaterials,properties and quality of interfaces hugely impact the performance of advanced semiconductors.Here,the effect of interfaces is explored by comparatively studying two InAs/AlSb superlattices with and without the thin InAsSb layers inserted inside each InAs layers.Through strain mapping,it indicates that the addition of interfaces leads to an increase of local strain both near interfaces and inside layers.Meantime,owing to the creation of hole potential wells within the original electron wells,the charge distribution undergoes an extra electron-hole alternating arrangement in the structure with inserted layers than the uninserted counterpart.Such a feature is verified to enhance electron-hole wave function overlap by theoretical simulations,which is a must for better optical performance.Furthermore,with an elaborate design of the inserted layers,the wave function overlap could be boosted without sacrificing other key device performances.展开更多
ZnO nanoparticles, 10-20 nm in size, were synthesized by heat treatment in air at 500 ℃ for 5 h., using [N,N＇-bis（salicylaldehydo） ethylene diamine]zinc（II）, i.e., Zn（salen）, as precursor, which was obtained b...ZnO nanoparticles, 10-20 nm in size, were synthesized by heat treatment in air at 500 ℃ for 5 h., using [N,N＇-bis（salicylaldehydo） ethylene diamine]zinc（II）, i.e., Zn（salen）, as precursor, which was obtained by a solvent-flee solid-solid reaction. Heat-treated products were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and transmission electron microscopy. Room temperature photoluminescence spectra of ZnO nanostructures are dominated by green emission attributed to oxygen vacancy related donor-acceptor transition.展开更多
Constructing a core-shell nanostructured photocatalyst by integration of plasmonic metal nanocrystals and a semiconductor can offer large active metal/semiconductor interfacial areas and avoid aggregation of the metal...Constructing a core-shell nanostructured photocatalyst by integration of plasmonic metal nanocrystals and a semiconductor can offer large active metal/semiconductor interfacial areas and avoid aggregation of the metal nanocrystals.Herein,well-defined Au@ZnO core-shell nanostructures were prepared by coating ZnO on cetyltrimethylammonium bromide(CTAB)stabilized Au nanospheres in aqueous solution.The resultant core-shell nanostructures have Au-nanosphere cores with a diameter of~55 nm and ZnO shells with a thickness of~50 nm.After calcination at 350℃in air,the mesoporous ZnO shell with higher crystallinity and a larger surface area was obtained without any significant change in the morphology or plasmon band of Au@ZnO.The specific surface plasmon resonance of the Au-nanosphere cores endows the Au@ZnO nanostructures with strong visible light absorption around 550 nm.The photocatalytic degradation of an organic pollutant was performed under simulated sunlight and monochromatic LED light with three different wavelengths(365 nm,520 nm,660 nm),demonstrating the enhanced photocatalysis of the Au@ZnO nanostructures.Furthermore,the Au@ZnO as a photoelectrode material presents a higher photocurrent density than that of pure ZnO nanoparticles under simulated sunlight.The electrochemical impedance spectra(EIS)Nyquist plots also confirm the higher charge transfer efficiency of the Au@ZnO nanostructures.Such plasmonic metal-semiconductor core-shell nanostructures would provide a desirable platform for studying plasmon-induced/enhanced processes and have great potential in light-harvesting applications.展开更多
The rational design of semiconductor nanostructures is of utmost importance for efficient solar energy conversion and environmental remediation.In this article,we report high-surface-area mesoporous networks consistin...The rational design of semiconductor nanostructures is of utmost importance for efficient solar energy conversion and environmental remediation.In this article,we report high-surface-area mesoporous networks consisting of Ni-implanted cubic CoO(Co_(1−x)Ni_(x)O)nanoparticles as promising catalysts for the detoxification of aqueous Cr(VI)solutions.Mechanistic studies with X-ray photoelectron,UV-vis optical absorption,fluorescence and electrochemical impedance spectroscopy and theoretical(DFT)calculations indicate that the performance enhancement of these catalysts arises from the high charge transfer kinetics and oxidation efficiency of surface-reaching holes.By tuning the chemical composition,the Co_(1−x)Ni_(x)O mesoporous catalyst at 2 atomic%Ni content imparts outstanding photocatalytic Cr(VI)reduction and water oxidation activity,corresponding to an apparent quantum yield(QY)of 1.5%atλ=375 nm irradiation light.展开更多
Effective construction of semiconductor hetero-nanostructures(HNSs)with a well-defined hetero-interface is of great importance.So far,highly developed liquid-phase chemical routes are often restricted by their heavy u...Effective construction of semiconductor hetero-nanostructures(HNSs)with a well-defined hetero-interface is of great importance.So far,highly developed liquid-phase chemical routes are often restricted by their heavy use of surfactants and/or organic solvents,which inevitably introduce passivated surfaces and interfacial defects in the resultant HNSs.Here,we have developed a novel and efficient in situ epitaxial growth strategy to fabricate HNSs of Ag_(3)PO_(4)quantum dots(QDs)on the external surface of hematite(Fe_(2)O_(3))nanotubes(NTs)(Ag_(3)PO_(4)/Fe_(2)O_(3)NT-HNSs),by intentionally employing chemically adsorbed phosphate anions on the surface of Fe_(2)O_(3)NTs to control the reaction kinetics of phosphate anions and Ag^(+)ions in aqueous solution.In this synthetic strategy,the chemically adsorbed phosphate anions on the surface of the Fe_(2)O_(3)NTs play the dual functions of heterogeneous nucleation and in situ epitaxial growth of Ag_(3)PO_(4)QDs along the direction of(311)on the(113)crystal plane of Fe_(2)O_(3)NTs.That is,they precipitate Ag^(+)ions via gradual dissociation of free phosphate anions and so generate Ag_(3)PO_(4)QDs,and they serve as a bridge and bond for in situ epitaxial growth of Ag_(3)PO_(4)QDs on Fe_(2)O_(3)NTs.Due to the unique coupling of the hetero-interfaces and internal electric field,the as-obtained Ag_(3)PO_(4)/Fe_(2)O_(3)NT-HNSs show efficient separation of photogenerated charge carriers and remarkable enhancement of their reduction and oxidation abilities by a Z-scheme photocatalytic form,significantly improving visible-light photocatalytic activity for decolorization of the organic pollutant rhodamine B.They exhibit a photocatalytic rate constant as large as 3.6×10^(-2) min^(-1),which is two orders of magnitude greater than that of single Fe_(2)O_(3)NTs(9.1×10^(-4) min^(-1)),single Ag_(3)PO_(4)QDs(1.6×10^(-4) min^(-1))as well as the mixture of the two(7.1×10^(-4) min^(-1)),suggesting a highly efficient photocatalyst.The in situ epitaxial growth strategy proposed here constitutes a novel example for fine construction of hetero-nanostructures for solar utilization.展开更多
文摘The efficiency of nanoscale nonlinear elements in photonic integrated circuits is hindered by the physical limits to the nonlinear optical response of dielectrics,which cannot be engineered as it is a fundamental material property.Here,we experimentally demonstrate that ultrafast optical nonlinearities in doped semiconductors can be engineered and can easily exceed those of conventional undoped dielectrics.The electron response of heavily doped semiconductors acquires in fact a hydrodynamic character that introduces nonlocal effects as well as additional nonlinear sources.Our experimental findings are supported by a comprehensive computational analysis based on the hydrodynamic model.In particular,by studying third-harmonic generation from plasmonic nanoantenna arrays made out of heavily n-doped InGaAs with increasing levels of free-carrier density,we discriminate between hydrodynamic and dielectric nonlinearities.Most importantly,we demonstrate that the maximum nonlinear efficiency as well as its spectral location can be engineered by tuning the doping level.Crucially,the maximum efficiency can be increased by almost two orders of magnitude with respect to the classical dielectric nonlinearity.Having employed the common material platform InGaAs/InP that supports integrated waveguides,our findings pave the way for future exploitation of plasmonic nonlinearities in all-semiconductor photonic integrated circuits.
文摘Semiconductor nanostructures have gained importance due to their potential application in future nano- electronic devices. For such applications, it is extremely important to understand the electrical properties of semi- conductor nanostructures. This review presents an overview of techniques to measure the electrical properties of individual and clusters of semiconductor nanostructures using microcopy based techniques or by fabricating metal- lic electrical contacts using lithography. Then it is shown that current-voltage （I-V） characteristics can be used to determine the conduction mechanism in these nanostructures. It has been explained that various material paramet- ers can be extracted from I-V characteristics. The frequently observed conduction mechanism in these nanostruc- tures such as thermally activated conduction, space charge limited current （SCLC）, hopping conduction, Poole Frenkel conduction, Schottky emission and Fowler Nordheim （FN） tunneling are explained in detail.
基金supported by the National Natural Science Foundation of China (51871104)the Fundamental Research Funds for the Central Universities (No.2019kfy RCPY074)。
文摘As the scaling down of semiconductor devices, it would be necessary to discover the structure-property relationship of semiconductor nanomaterials at nanometer scale. In this review, the quantitative characterization technique off-axis electron holography is introduced in details, followed by its applications in various semiconductor nanomaterials including group IV, compound and two-dimensional semiconductor nanostructures in static states as well as under various stimuli. The advantages and disadvantages of off-axis electron holography in material analysis are discussed, the challenges facing in-situ electron holographic study of semiconductor devices at working conditions are presented, and all the possible influencing factors need to be considered to achieve the final goal of fulfilling quantitative characterization of the structure-property relationship of semiconductor devices at their working conditions.
基金Supported by the National Key Technology Research and Development Program under Grant No 2016YFB0400100the National Basic Research Program of China under Grant No 2012CB619304+4 种基金the High-Technology Research and Development Program of China under Grant Nos 2014AA032605 and 2015AA033305the National Natural Science Foundation of China under Grant Nos61274003,61422401,51461135002 and 61334009the Key Technology Research of Jiangsu Province under Grant No BE2015111the Solid State Lighting and Energy-Saving Electronics Collaborative Innovation Centerthe Research Funds from NJU-Yangzhou Institute of Opto-electronics
文摘GaN nanorods are fabricated using inductively coupled plasma etching with Ni nano-island masks. The poly [2- methoxy-5-（2-ethyl）hexoxy-l,4-phenylenevinylene] （MEH-PPV）/GaN-nanorod hybrid structure is fabricated by depositing the MEH-PPV film on the GaN nanorods by using the spin-coating process. In the hybrid structure, the spatial separation is minimized to achieve high-emciency non-radiative resonant energy transfer. Optical properties of a novel device consisting of MEH-PPV/GaN-nanorod hybrid structure is studied by analyzing photoluminescenee （PL） spectra. Compared with the pure GaN nanorods, the PL intensity of the band edge emission of GaN in the MEH-PPV/GaN-nanorods is enhanced as much as three times, and the intensity of the yellow band is suppressed slightly. The obtained results are analyzed by energy transfer between the GaN nanorods and the MEH-PPV. An energy transfer model is proposed to explain the phenomenon.
基金supported by the China Scholarship Council (CSC) (No.20083019)Fundamental Research Funds for the Central Universities (Nos.21611603,21611424,and 216113143)+1 种基金Jinan University Start-up Funds (No.50624019)the Knowledge Innovation Program of the Chinese Academy of Sciences (No.KJCX2-YW-M13)
文摘ZnO tetrapods were synthesized by a typical thermal vapor-solid deposition method in a horizontal tube furnace.Structural characterization was carried out by transmission electron microscopy （TEM） and select-area electron diffraction （SAED）,which shows the presence of zinc blende nucleus in the center of tetrapods while the four branches taking hexagonal wurtzite structure.The electrical transport property of ZnO tetrapods was investigated through an in-situ nanoprobe system.The three branches of a tetrapod serve as source,drain,and ＂gate＂,respectively;while the fourth branch pointing upward works as the force trigger by vertically applying external force downward.The conductivity of each branch of ZnO-tetrapods increases 3-4 times under pressure.In such situation,the electrical current through the branches of ZnO tetrapods can be tuned by external force,and therefore a simple force sensor based on ZnO tetrapods has been demonstrated for the first time.
文摘In this paper we analyze a long standing problem of the appearance of spurious,non-physical solutions arising in the application of the effective mass theory to low dimensional nanostructures.The theory results in a system of coupled eigenvalue PDEs that is usually supplemented by interface boundary conditions that can be derived from a variational formulation of the problem.We analyze such a system for the envelope functions and show that a failure to restrict their Fourier expansion coeffi-cients to small k components would lead to the appearance of non-physical solutions.We survey the existing methodologies to eliminate this difficulty and propose a simple and effective solution.This solution is demonstrated on an example of a two-band model for both bulk materials and low-dimensional nanostructures.Finally,based on the above requirement of small k,we derive a model for nanostructures with cylindrical symmetry and apply the developed model to the analysis of quantum dots using an eight-band model.
基金This work was supported by the Ministry of Science and Technology of China(No.2018YFA0209102)the National Natural Science Foundation of China(Nos.11727807,51725101,51672050,and 61790581).
文摘As the proportion of interfaces increases rapidly in nanomaterials,properties and quality of interfaces hugely impact the performance of advanced semiconductors.Here,the effect of interfaces is explored by comparatively studying two InAs/AlSb superlattices with and without the thin InAsSb layers inserted inside each InAs layers.Through strain mapping,it indicates that the addition of interfaces leads to an increase of local strain both near interfaces and inside layers.Meantime,owing to the creation of hole potential wells within the original electron wells,the charge distribution undergoes an extra electron-hole alternating arrangement in the structure with inserted layers than the uninserted counterpart.Such a feature is verified to enhance electron-hole wave function overlap by theoretical simulations,which is a must for better optical performance.Furthermore,with an elaborate design of the inserted layers,the wave function overlap could be boosted without sacrificing other key device performances.
基金the councils of Iran National Science Foundation and University of Kashan for their unending effort inproviding financial support in this work
文摘ZnO nanoparticles, 10-20 nm in size, were synthesized by heat treatment in air at 500 ℃ for 5 h., using [N,N＇-bis（salicylaldehydo） ethylene diamine]zinc（II）, i.e., Zn（salen）, as precursor, which was obtained by a solvent-flee solid-solid reaction. Heat-treated products were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and transmission electron microscopy. Room temperature photoluminescence spectra of ZnO nanostructures are dominated by green emission attributed to oxygen vacancy related donor-acceptor transition.
基金supported by the National Natural Science Foundation of China(21471004)the China Postdoctoral Science Foundation of Special Funding(2015T80644)the Excellent Youth Talents Support Plan in Colleges and Universities of Anhui Province.
文摘Constructing a core-shell nanostructured photocatalyst by integration of plasmonic metal nanocrystals and a semiconductor can offer large active metal/semiconductor interfacial areas and avoid aggregation of the metal nanocrystals.Herein,well-defined Au@ZnO core-shell nanostructures were prepared by coating ZnO on cetyltrimethylammonium bromide(CTAB)stabilized Au nanospheres in aqueous solution.The resultant core-shell nanostructures have Au-nanosphere cores with a diameter of~55 nm and ZnO shells with a thickness of~50 nm.After calcination at 350℃in air,the mesoporous ZnO shell with higher crystallinity and a larger surface area was obtained without any significant change in the morphology or plasmon band of Au@ZnO.The specific surface plasmon resonance of the Au-nanosphere cores endows the Au@ZnO nanostructures with strong visible light absorption around 550 nm.The photocatalytic degradation of an organic pollutant was performed under simulated sunlight and monochromatic LED light with three different wavelengths(365 nm,520 nm,660 nm),demonstrating the enhanced photocatalysis of the Au@ZnO nanostructures.Furthermore,the Au@ZnO as a photoelectrode material presents a higher photocurrent density than that of pure ZnO nanoparticles under simulated sunlight.The electrochemical impedance spectra(EIS)Nyquist plots also confirm the higher charge transfer efficiency of the Au@ZnO nanostructures.Such plasmonic metal-semiconductor core-shell nanostructures would provide a desirable platform for studying plasmon-induced/enhanced processes and have great potential in light-harvesting applications.
基金Special Account for Research Funds of the University of Crete(SARF UOC)(KA 10138)。
文摘The rational design of semiconductor nanostructures is of utmost importance for efficient solar energy conversion and environmental remediation.In this article,we report high-surface-area mesoporous networks consisting of Ni-implanted cubic CoO(Co_(1−x)Ni_(x)O)nanoparticles as promising catalysts for the detoxification of aqueous Cr(VI)solutions.Mechanistic studies with X-ray photoelectron,UV-vis optical absorption,fluorescence and electrochemical impedance spectroscopy and theoretical(DFT)calculations indicate that the performance enhancement of these catalysts arises from the high charge transfer kinetics and oxidation efficiency of surface-reaching holes.By tuning the chemical composition,the Co_(1−x)Ni_(x)O mesoporous catalyst at 2 atomic%Ni content imparts outstanding photocatalytic Cr(VI)reduction and water oxidation activity,corresponding to an apparent quantum yield(QY)of 1.5%atλ=375 nm irradiation light.
基金supported by the National Natural Science Foundation of China(21705123,51573144,and 51521001)the Top Talents Lead Cultivation Project of Hubei Province.
文摘Effective construction of semiconductor hetero-nanostructures(HNSs)with a well-defined hetero-interface is of great importance.So far,highly developed liquid-phase chemical routes are often restricted by their heavy use of surfactants and/or organic solvents,which inevitably introduce passivated surfaces and interfacial defects in the resultant HNSs.Here,we have developed a novel and efficient in situ epitaxial growth strategy to fabricate HNSs of Ag_(3)PO_(4)quantum dots(QDs)on the external surface of hematite(Fe_(2)O_(3))nanotubes(NTs)(Ag_(3)PO_(4)/Fe_(2)O_(3)NT-HNSs),by intentionally employing chemically adsorbed phosphate anions on the surface of Fe_(2)O_(3)NTs to control the reaction kinetics of phosphate anions and Ag^(+)ions in aqueous solution.In this synthetic strategy,the chemically adsorbed phosphate anions on the surface of the Fe_(2)O_(3)NTs play the dual functions of heterogeneous nucleation and in situ epitaxial growth of Ag_(3)PO_(4)QDs along the direction of(311)on the(113)crystal plane of Fe_(2)O_(3)NTs.That is,they precipitate Ag^(+)ions via gradual dissociation of free phosphate anions and so generate Ag_(3)PO_(4)QDs,and they serve as a bridge and bond for in situ epitaxial growth of Ag_(3)PO_(4)QDs on Fe_(2)O_(3)NTs.Due to the unique coupling of the hetero-interfaces and internal electric field,the as-obtained Ag_(3)PO_(4)/Fe_(2)O_(3)NT-HNSs show efficient separation of photogenerated charge carriers and remarkable enhancement of their reduction and oxidation abilities by a Z-scheme photocatalytic form,significantly improving visible-light photocatalytic activity for decolorization of the organic pollutant rhodamine B.They exhibit a photocatalytic rate constant as large as 3.6×10^(-2) min^(-1),which is two orders of magnitude greater than that of single Fe_(2)O_(3)NTs(9.1×10^(-4) min^(-1)),single Ag_(3)PO_(4)QDs(1.6×10^(-4) min^(-1))as well as the mixture of the two(7.1×10^(-4) min^(-1)),suggesting a highly efficient photocatalyst.The in situ epitaxial growth strategy proposed here constitutes a novel example for fine construction of hetero-nanostructures for solar utilization.
