A facile one-step hydrothermal method has been reported to synthesize theα-Fe_(2)O_(3)nanosheet arrays with the preferred orientation along the[104]direction on the ITO substrate.Theα-Fe_(2)O_(3)nanosheet arrays-bas...A facile one-step hydrothermal method has been reported to synthesize theα-Fe_(2)O_(3)nanosheet arrays with the preferred orientation along the[104]direction on the ITO substrate.Theα-Fe_(2)O_(3)nanosheet arrays-based W/α-Fe_(2)O_(3)/ITO memristor has been achieved by depositing the circular W top electrodes on theα-Fe_(2)O_(3)nanosheet arrays.The as-prepared W/α-Fe_(2)O_(3)/ITO memristor shows a reliable nonvolatile bipolar resistive switching behavior with the high resistance ratio of about 103at the reading voltage of 0.1 V,good resistance retention over 10~3s,ultralow set voltage of-0.6 V and reset voltage of 0.7 V,and good durability.In addition,the tunneling conduction mechanism modified by the oxygen vacancies has been proposed and suggested to be responsible for the nonvolatile resistive switching behavior of the as-prepared W/α-Fe_(2)O_(3)/ITO memristor.This work demonstrates that the as-preparedα-Fe_(2)O_(3)nanosheet arrays-based W/α-Fe_(2)O_(3)/ITO memristor would be a promising candidate for further ultralow power nonvolatile memory applications.展开更多
The photo-assisted Fenton-like method is an effective and sustainable way to remove organic pollutants from water.Herein,a series of three-dimensional composites containing MIL-88A(Fe)-derived α-Fe_(2)O_(3)and graphe...The photo-assisted Fenton-like method is an effective and sustainable way to remove organic pollutants from water.Herein,a series of three-dimensional composites containing MIL-88A(Fe)-derived α-Fe_(2)O_(3)and graphene aerogel(GA-Fe-X)were designed and used as catalysts to degrade ciprofloxacin(CIP)by peroxymonosulfate(PMS)activated photo-Fenton-like technology.The as-prepared GA-Fe-1 displayed remarkable enhancement with a CIP degradation rate constant(0.017 min^(-1))higher than that of graphene aerogel(0.0031 min^(-1))and MIL-88A(Fe)(0.0039 min^(-1)).Experimental results demonstrated that the combination of MIL-88A(Fe)-derived α-Fe_(2)O_(3)and graphene aerogel forming GA-Fe-X enhanced the separation efficiency of electron-hole pairs,activating PMS to produce SO_(4)^(·-),^(·)OH and ^(1)O_(2) for enhanced CIP degradation through radical and non-radical pathways.The factors affecting CIP degradation during the photoFenton-like process were thoroughly investigated.The possible CIP degradation pathways and ecotoxicity of the intermediates were also analyzed.This work enhances our understanding of the photo-Fenton-like effect in three-dimensional graphene aerogel composites.展开更多
Even in small concentrations,toxic metals like lead,cadmium,and mercury are dangerous to the environment and human health.Environmental monitoring depends on precisely identifying these heavy metals,particularly cadmi...Even in small concentrations,toxic metals like lead,cadmium,and mercury are dangerous to the environment and human health.Environmental monitoring depends on precisely identifying these heavy metals,particularly cadmium ions(Cd(Ⅱ)).In this study,we present a novel screen-printed carbon electrode(SPCE)modified with single crystallineα-Fe_(2)O_(3)nano-hexagons that functions as a sensor for detecting Cd(Ⅱ).The performance of the fabricated sensor was thoroughly assessed and compared with unmodified SPCE using the voltammetric method.The crystalline structure of the synthesizedα-Fe_(2)O_(3)nano-hexagons was confirmed through XRD,and surface analysis revealed an average diameter and thickness of 86 nm and 9 nm,respectively.Theα-Fe_(2)O_(3)modified SPCE yields a 7-fold enhanced response(at pH 5.0 vs.Ag/AgCl)to Cd(Ⅱ)than bare SPCE.The modified electrode effectively detects Cd(Ⅱ)with a linear response range of up to 333.0μmol/L and a detection limit of 0.65 nmol/L under ideal circumstances.This newly fabricated sensor offers significant potential for environmental monitoring applications by providing outstanding practicality,anti-interference ability,and repeatability for detecting Cd(Ⅱ)in water samples.展开更多
We present a self-assembly method to prepare array nano-wires of colloidal CdSe quantum dots on a substrate of porous Al_(2)O_(3) film modified by gold nanoparticles.The photoluminescence(PL)spectra of nanowires are i...We present a self-assembly method to prepare array nano-wires of colloidal CdSe quantum dots on a substrate of porous Al_(2)O_(3) film modified by gold nanoparticles.The photoluminescence(PL)spectra of nanowires are in situ measured by using a scanning near-field optical microscopy(SNOM)probe tip with 100-nm aperture on the scanning near-field optical microscope.The results show that the binding sites from the edge of porous Al_(2)O_(3) nanopores are combined with the carboxyl of CdSe quantum dots’surface to form an array of CdSe nanowires in the process of losing background solvent because of the gold nanoparticles filling the nano-holes of porous Al_(2)O_(3) film.Compared with the area of nonself-assembled nano-wire,the fluorescence on the Al_(2)O_(3)/Au/CdSe interface is significantly enhanced in the self-assembly nano-wire regions due to the electron transfer conductor effect of the gold nanoparticles’surface.In addition,its full width at half maximum(FWHM)is also obviously widened.The method of enhancing fluorescence and energy transfer can widely be applied to photodetector,photocatalysis,optical display,optical sensing,and biomedical imaging,and so on.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.62341305 and 22269002)the Natural Science Foundation of Guangxi Zhuang Autonomous Region,China(Grant No.2024GXNSFFA010007)+2 种基金the Science and Technology Project of Guangxi Zhuang Autonomous Region,China(Grant No.AD19110038)the Key Laboratory of AI and Information Processing,Education Department of Guangxi Zhuang Autonomous Region(Grant No.2024GXZDSY015)the Innovation Project of Guangxi University of Science and Technology Graduate Education(Grant No.GKYC202408)。
文摘A facile one-step hydrothermal method has been reported to synthesize theα-Fe_(2)O_(3)nanosheet arrays with the preferred orientation along the[104]direction on the ITO substrate.Theα-Fe_(2)O_(3)nanosheet arrays-based W/α-Fe_(2)O_(3)/ITO memristor has been achieved by depositing the circular W top electrodes on theα-Fe_(2)O_(3)nanosheet arrays.The as-prepared W/α-Fe_(2)O_(3)/ITO memristor shows a reliable nonvolatile bipolar resistive switching behavior with the high resistance ratio of about 103at the reading voltage of 0.1 V,good resistance retention over 10~3s,ultralow set voltage of-0.6 V and reset voltage of 0.7 V,and good durability.In addition,the tunneling conduction mechanism modified by the oxygen vacancies has been proposed and suggested to be responsible for the nonvolatile resistive switching behavior of the as-prepared W/α-Fe_(2)O_(3)/ITO memristor.This work demonstrates that the as-preparedα-Fe_(2)O_(3)nanosheet arrays-based W/α-Fe_(2)O_(3)/ITO memristor would be a promising candidate for further ultralow power nonvolatile memory applications.
基金National Natural Science Foundation of China(Nos.12075152,42177405,12075147)for the financial support。
文摘The photo-assisted Fenton-like method is an effective and sustainable way to remove organic pollutants from water.Herein,a series of three-dimensional composites containing MIL-88A(Fe)-derived α-Fe_(2)O_(3)and graphene aerogel(GA-Fe-X)were designed and used as catalysts to degrade ciprofloxacin(CIP)by peroxymonosulfate(PMS)activated photo-Fenton-like technology.The as-prepared GA-Fe-1 displayed remarkable enhancement with a CIP degradation rate constant(0.017 min^(-1))higher than that of graphene aerogel(0.0031 min^(-1))and MIL-88A(Fe)(0.0039 min^(-1)).Experimental results demonstrated that the combination of MIL-88A(Fe)-derived α-Fe_(2)O_(3)and graphene aerogel forming GA-Fe-X enhanced the separation efficiency of electron-hole pairs,activating PMS to produce SO_(4)^(·-),^(·)OH and ^(1)O_(2) for enhanced CIP degradation through radical and non-radical pathways.The factors affecting CIP degradation during the photoFenton-like process were thoroughly investigated.The possible CIP degradation pathways and ecotoxicity of the intermediates were also analyzed.This work enhances our understanding of the photo-Fenton-like effect in three-dimensional graphene aerogel composites.
文摘Even in small concentrations,toxic metals like lead,cadmium,and mercury are dangerous to the environment and human health.Environmental monitoring depends on precisely identifying these heavy metals,particularly cadmium ions(Cd(Ⅱ)).In this study,we present a novel screen-printed carbon electrode(SPCE)modified with single crystallineα-Fe_(2)O_(3)nano-hexagons that functions as a sensor for detecting Cd(Ⅱ).The performance of the fabricated sensor was thoroughly assessed and compared with unmodified SPCE using the voltammetric method.The crystalline structure of the synthesizedα-Fe_(2)O_(3)nano-hexagons was confirmed through XRD,and surface analysis revealed an average diameter and thickness of 86 nm and 9 nm,respectively.Theα-Fe_(2)O_(3)modified SPCE yields a 7-fold enhanced response(at pH 5.0 vs.Ag/AgCl)to Cd(Ⅱ)than bare SPCE.The modified electrode effectively detects Cd(Ⅱ)with a linear response range of up to 333.0μmol/L and a detection limit of 0.65 nmol/L under ideal circumstances.This newly fabricated sensor offers significant potential for environmental monitoring applications by providing outstanding practicality,anti-interference ability,and repeatability for detecting Cd(Ⅱ)in water samples.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61741505 and 61865002)the Guizhou Provincial Science and Technology Support Plan,China(Grant No QKHZ[2017]2887)+3 种基金the Guiding Local Science and Technology Development Plan of the Central Government of China(Grant No.QKZYD[2017]4004)the Guizhou Province Education and Teaching Reform for Graduate Student(Grant No.QJYH-JG[2016]15)the Guizhou University Introduces Talent Projects,China(Grant No.2016002)the Talents of Guizhou Municipal Science and Technology Cooperation Platform,China(Grant No.[2018]5781)
文摘We present a self-assembly method to prepare array nano-wires of colloidal CdSe quantum dots on a substrate of porous Al_(2)O_(3) film modified by gold nanoparticles.The photoluminescence(PL)spectra of nanowires are in situ measured by using a scanning near-field optical microscopy(SNOM)probe tip with 100-nm aperture on the scanning near-field optical microscope.The results show that the binding sites from the edge of porous Al_(2)O_(3) nanopores are combined with the carboxyl of CdSe quantum dots’surface to form an array of CdSe nanowires in the process of losing background solvent because of the gold nanoparticles filling the nano-holes of porous Al_(2)O_(3) film.Compared with the area of nonself-assembled nano-wire,the fluorescence on the Al_(2)O_(3)/Au/CdSe interface is significantly enhanced in the self-assembly nano-wire regions due to the electron transfer conductor effect of the gold nanoparticles’surface.In addition,its full width at half maximum(FWHM)is also obviously widened.The method of enhancing fluorescence and energy transfer can widely be applied to photodetector,photocatalysis,optical display,optical sensing,and biomedical imaging,and so on.