The preparation of polyaniline nanofibers in aqueous solution was studied as functions of the concentrations and ratios of reactants. The morphology and microstructure of polyaniline nanofibers are affected by the con...The preparation of polyaniline nanofibers in aqueous solution was studied as functions of the concentrations and ratios of reactants. The morphology and microstructure of polyaniline nanofibers are affected by the concentrations and proportions of the reactants. A special kind of sea cucumber-like polyaniline nanofibers can be prepared under control of reaction conditions. Secondary growth is the formation mechanism. In addition, the bulk electrical conductivity of these sea cucumber-like polyaniline nanofibers was higher than that of other common polyaniline nanofibers.展开更多
Cu nanoparticles were prepared by reducing Cu2＋ ions with ascorbic acid through aqueous solution reduction method. The effects of solution pH and average size of Cu2O particles on the preparation of Cu nanoparticles ...Cu nanoparticles were prepared by reducing Cu2＋ ions with ascorbic acid through aqueous solution reduction method. The effects of solution pH and average size of Cu2O particles on the preparation of Cu nanoparticles were investigated. Cu particles were prepared at pH 3, 5 or 7, with the smallest Cu particles obtained at pH 7. However, Cu particles could not be prepared at pH 9 or 11. The average size of Cu2O particles can affect that of Cu particles. Larger Cu2O particles result in larger Cu particles. In addition, experiments were conducted to explore the reaction process by measuring the X-ray diffraction （XRD） patterns of specimens collected at different time points during the reaction. It was found that Cu（OH）2 was initially formed as a precursor, followed by the formation of Cu2O, which was finally reduced to Cu particles.展开更多
The preparation of Cu nanoparticles by the aqueous solution reduction method was investigated. The effects of different reaction parameters on the preparation of Cu nanoparticles were studied. The optimum conditions f...The preparation of Cu nanoparticles by the aqueous solution reduction method was investigated. The effects of different reaction parameters on the preparation of Cu nanoparticles were studied. The optimum conditions for preparing well-dispersed nanoparticles were found as follows: 0.4 mol/L NaBH4 was added into solution containing 0.2 mol/L Cu2+, 1.0% gelatin dispersant in mass fraction, and 1.2 mol/L NH3?H2O at pH 12 and 313 K. In addition, a series of experiments were performed to discover the reaction process. NH3?H2O was found to be able to modulate the reaction process. At pH=10, Cu2+ was transformed to Cu(NH3)42+ as precursor after the addition of NH3?H2O, and then Cu(NH3)42+ was reduced by NaBH4 solution. At pH=12, Cu2+ was transformed to Cu(OH)2 as precursor after the addition of NH3?H2O, and Cu(OH)2 was then reduced by NaBH4 solution.展开更多
In this paper,a novel electrochemical sensor based on a functionalized multi-walled carbon nanotube(f-MWCNT)decorated ruskin michelle-like zinc oxide(ZnO)nanocomposite for the determination of the environmental pollut...In this paper,a novel electrochemical sensor based on a functionalized multi-walled carbon nanotube(f-MWCNT)decorated ruskin michelle-like zinc oxide(ZnO)nanocomposite for the determination of the environmental pollutant hydroquinone(HQ)is reported.We have followed a new aqueous solution method for the synthesis of ruskin michelle-like ZnO nanoparticles and they are characterized by scanning electron microscopy(SEM),X-ray diffraction(XRD),Raman spectroscopy,Fourier transform infrared(FT-IR)spectroscopy and UV visible spectroscopy.Cyclic voltammetry(CV),differential pulse voltammetry(DPV)and amperometric techniques are used for the electrochemical analysis of a f-MWCNT decorated ruskin michelle-like ZnO nanocomposite modified glassy carbon electrode(GCE).The fabricated f-MWCNT/ZnO GCE showcased excellent electrocatalytic activity in the determination of HQ and we obtained a sharp anodic and cathodic peak current at a low potential value of 0.11 V and 0.05 V,respectively.Efficient reproducibility and stability,anti-interference property and good repeatability,which are the traits of a good electrochemical sensor,are exhibited by the fabricated sensor.We have obtained a very low limit of detection(LOD)for the fabricated f-MWCNT/ZnO GCE of 0.02μM,a linear response in the range of 0.1-190μM and a sensitivity of 6.37μAμM^(-1)cm^(-2).These results obtained from the electrochemical analysis reveal the excellent performance of the f-MWCNT decorated ruskin michelle-like ZnO nanocomposite modified GCE in the effective determination of HQ.展开更多
基金supported by the National Advanced Materials Committee of China (No. 2008AA03Z409)
文摘The preparation of polyaniline nanofibers in aqueous solution was studied as functions of the concentrations and ratios of reactants. The morphology and microstructure of polyaniline nanofibers are affected by the concentrations and proportions of the reactants. A special kind of sea cucumber-like polyaniline nanofibers can be prepared under control of reaction conditions. Secondary growth is the formation mechanism. In addition, the bulk electrical conductivity of these sea cucumber-like polyaniline nanofibers was higher than that of other common polyaniline nanofibers.
文摘Cu nanoparticles were prepared by reducing Cu2＋ ions with ascorbic acid through aqueous solution reduction method. The effects of solution pH and average size of Cu2O particles on the preparation of Cu nanoparticles were investigated. Cu particles were prepared at pH 3, 5 or 7, with the smallest Cu particles obtained at pH 7. However, Cu particles could not be prepared at pH 9 or 11. The average size of Cu2O particles can affect that of Cu particles. Larger Cu2O particles result in larger Cu particles. In addition, experiments were conducted to explore the reaction process by measuring the X-ray diffraction （XRD） patterns of specimens collected at different time points during the reaction. It was found that Cu（OH）2 was initially formed as a precursor, followed by the formation of Cu2O, which was finally reduced to Cu particles.
文摘The preparation of Cu nanoparticles by the aqueous solution reduction method was investigated. The effects of different reaction parameters on the preparation of Cu nanoparticles were studied. The optimum conditions for preparing well-dispersed nanoparticles were found as follows: 0.4 mol/L NaBH4 was added into solution containing 0.2 mol/L Cu2+, 1.0% gelatin dispersant in mass fraction, and 1.2 mol/L NH3?H2O at pH 12 and 313 K. In addition, a series of experiments were performed to discover the reaction process. NH3?H2O was found to be able to modulate the reaction process. At pH=10, Cu2+ was transformed to Cu(NH3)42+ as precursor after the addition of NH3?H2O, and then Cu(NH3)42+ was reduced by NaBH4 solution. At pH=12, Cu2+ was transformed to Cu(OH)2 as precursor after the addition of NH3?H2O, and Cu(OH)2 was then reduced by NaBH4 solution.
基金supported by the Ministry of Science and Technology,ROC,under grant no.105-2221-E-027-061.
文摘In this paper,a novel electrochemical sensor based on a functionalized multi-walled carbon nanotube(f-MWCNT)decorated ruskin michelle-like zinc oxide(ZnO)nanocomposite for the determination of the environmental pollutant hydroquinone(HQ)is reported.We have followed a new aqueous solution method for the synthesis of ruskin michelle-like ZnO nanoparticles and they are characterized by scanning electron microscopy(SEM),X-ray diffraction(XRD),Raman spectroscopy,Fourier transform infrared(FT-IR)spectroscopy and UV visible spectroscopy.Cyclic voltammetry(CV),differential pulse voltammetry(DPV)and amperometric techniques are used for the electrochemical analysis of a f-MWCNT decorated ruskin michelle-like ZnO nanocomposite modified glassy carbon electrode(GCE).The fabricated f-MWCNT/ZnO GCE showcased excellent electrocatalytic activity in the determination of HQ and we obtained a sharp anodic and cathodic peak current at a low potential value of 0.11 V and 0.05 V,respectively.Efficient reproducibility and stability,anti-interference property and good repeatability,which are the traits of a good electrochemical sensor,are exhibited by the fabricated sensor.We have obtained a very low limit of detection(LOD)for the fabricated f-MWCNT/ZnO GCE of 0.02μM,a linear response in the range of 0.1-190μM and a sensitivity of 6.37μAμM^(-1)cm^(-2).These results obtained from the electrochemical analysis reveal the excellent performance of the f-MWCNT decorated ruskin michelle-like ZnO nanocomposite modified GCE in the effective determination of HQ.
