In this work, we fabricated the polyaniline/silver nanoparticle/multi-walled carbon nanotube （PANI/Ag/MWCNT） composites by in situ polymerization of aniline on the wall of Ag/MWCNTs with different aniline to Ag/MWCN...In this work, we fabricated the polyaniline/silver nanoparticle/multi-walled carbon nanotube （PANI/Ag/MWCNT） composites by in situ polymerization of aniline on the wall of Ag/MWCNTs with different aniline to Ag/MWCNT mass ratios. The chemical structure of the ternary composites was characterized by Fourier transform infrared spectroscopy, Xray diffraction, and X-ray photoelectron spectroscopy. Scanning electron microscope and high-resolution transmission electron microscopy were used to observe the morphology of the ternary composites. The results showed that the polyaniline PANI layer was prepared successfully and it covered Ag/MWCNTs completely. In addition, Ag nanoparticles between the MWCNT core and the PANI layer existed in the form of elemental crystal, which could contribute to the electrochemical performance of the composites. Then we prepared the composite electrodes and studied their electrochemical behaviors in 1 mol/L KOH. It was found that these composite electrodes had very low impedance, and exhibited lower resistance, higher electrochemical activity, and better cyclic stability compared with pure PANI electrode. Particularly, when the mass ratio of aniline to Ag/MWCNTs was 5：5, the composite electrode displayed a small equivalent series resistance （0.23 Ω） and low interfacial charge transfer resistance （〈0.25 Ω）, as well as 160 F/g of the maximum specific capacitance at a current density of 0.25 A/g in KOH solution. We could conclude that the composite material had potential applications as cathode materials for lithium batteries and supercapacitors.展开更多
The thermal radiation energy is the clean energy with a much lower environmental impact than the conventional energy. The objective of the present work is to investigate theoretically the effect of copper nanoparticle...The thermal radiation energy is the clean energy with a much lower environmental impact than the conventional energy. The objective of the present work is to investigate theoretically the effect of copper nanoparticles and carbon nanotubes （CNTs） in the presence of base fluid （water） with the variable stream condition due to the thermal radiation energy. Single-walled carbon nanotubes （SWCNTs） in the presence of base fluid flow over a porous wedge play a significant role compared to those of copper nanoparticles on absorbing the incident solar radiation and transiting it to the working fluid by convection.展开更多
Copper nanoparticles-decorated polyaniline- derived mesoporous carbon that can serve as noble metal-free electrocatalyst for the hydrazine oxidation reaction （HzOR） is synthesized via a facile synthetic route. The m...Copper nanoparticles-decorated polyaniline- derived mesoporous carbon that can serve as noble metal-free electrocatalyst for the hydrazine oxidation reaction （HzOR） is synthesized via a facile synthetic route. The material exhibits excellent electrocatalytic activity toward HzOR with low overpotential and high current density. The material also remains stable during the electrocatalytic reaction for long time. Its good electro- catalytic performance makes this material a promising alternative to conventional noble metal-based catalysts （e.g., Pt） that are commonly used in HzOR-based fuel cells.展开更多
The multiwalled carbon nanotubes thin-film-based electrode was fabricated by electrophoretic deposition and modified with copper （Cu） nanoparticles to fabricate Cu/CNTs nanocomposite sensor for nonenzymatic glucose ...The multiwalled carbon nanotubes thin-film-based electrode was fabricated by electrophoretic deposition and modified with copper （Cu） nanoparticles to fabricate Cu/CNTs nanocomposite sensor for nonenzymatic glucose detection. The expensive glassy carbon electrode was replaced by fluorine-doped tin oxide glass containing CNTs film to confine the Cu nanoparticles growth by electrodeposition through cyclic voltammetry （CV）. The ultraviolet visible and X-ray diffraction analysis revealed the successful deposition of Cu nanoparticles on the CNTs-modified electrode. The atomic force microscopy images confirrqed the morphology of electrodeposited Cu on CNTs film as uniformly dispersed particles. The electrocatalytic activity of electrode to the glucose oxidation was investigated in alkaline medium by CV and amperometric measurements. The fabricated sensor exhibited a fast response time of less than 5 s and the sensitivity of 314 μA rnM^-1 cm^-2 with linear concentration range （0.02-3.0 mM） having detection limit 10.0 μM. Due to simple preparation of sensor, Cu/CNTs nanocomposite electrodes are a suitable candidate for reliable determination of glucose with good stability.展开更多
A novel hybrid material, Cu-PAA/MWCNTs （copper nanoparticles deposited multiwalled carbon nano- tubes with poly （acrylic acid） as dispersant, was prepared and expected to obtain a more effective and well-dispersed ...A novel hybrid material, Cu-PAA/MWCNTs （copper nanoparticles deposited multiwalled carbon nano- tubes with poly （acrylic acid） as dispersant, was prepared and expected to obtain a more effective and well-dispersed disinfection material for water treatment. X-ray energy dispersive spectroscopy （EDS）, transmission electron microscopy （TEM）, the X-ray fluorescence （XRF）, X-ray photoelectron spectra （XPS）, Fourier transform infrared spectra （FT-IR）, Raman spectroscopy, and thermal gravi- metric analyzer （TGA） were used to characterize the Cu- PAA/MWCNTs. Escherichia coli （E. coil） was employed as the target bacteria. The cell viability determination and fluorescence imaging results demonstrated that Cu-PAA/ MWCNTs possessed strong antimicrobial ability on E. coil. The deposited Cu was suggested to play an important role in the antimicrobial action of Cu-PAA/MWCNTs.展开更多
Ag-Pt bimetallic nanoparticles decorated on MWCNTs/PANI nanocomposites have been synthesized by in-situ chemical oxidative polymerization and chemical co-reduction method. The Fourier transform infrared（FT-IR） spect...Ag-Pt bimetallic nanoparticles decorated on MWCNTs/PANI nanocomposites have been synthesized by in-situ chemical oxidative polymerization and chemical co-reduction method. The Fourier transform infrared（FT-IR） spectroscopy, X-ray diffraction（XRD）, ultraviolet-visible（UV-vis） absorption spectroscopy, scanning electron microscopy（SEM） and transmission electron microscopy（TEM） were used to characterize the morphology and structure of the nanocomposites. It can be observed that the PANI was uniformly grown along the MWCNTs to form MWCNsT/PANI fiber-like nanocomposites with diameter about 60 nm, and the Ag-Pt binary nanoparticles were decorated onto MWCNTs/PANI with particle sizes around 6.8 nm. Cyclic voltammetry（CV） and electrochemical impedance spectroscopy（EIS） were used to characterize the electrochemical performance of the prepared electrode. The results demonstrated that the obtained MWCNTs/PANI/Ag-Pt electrode displayed a good electrochemical activity and fast electron transport, which has potential applications in biosensors and supercapacitors.展开更多
Nanoparticles(NPs)are widely used for their special physical properties and released into the natural environment.When two types of NPs exist in the same environment,the presence of one type of NP may affect the prope...Nanoparticles(NPs)are widely used for their special physical properties and released into the natural environment.When two types of NPs exist in the same environment,the presence of one type of NP may affect the properties of the other type of NP.This study investigated the toxic effects of multi-walled carbon nanotubes(MWCNTs)and copper oxide nanoparticles(Cu O NPs)on Tetradesmus obliquus.Both NPs had toxic effects on algae,and the toxic effects of MWCNTs were significantly stronger than Cu O NPs which the 96-hr median effective concentration to algae were 33.8 and 169.2 mg/L,respectively.Oxidative stress and cell membrane damage were the main reasons for the toxicity of NPs to algae,and they were concentration-dependent,and the existence of Cu O NPs in some groups reduced cell membrane damage caused by MWCNTs which may because that Cu O NPs formed heteroaggregation with MWCNTs,reducing the contact of nanoparticles with cell membranes,then reducing physical damage.Scanning electron microscopy(SEM)and transmission electron microscope(TEM)results indicated cell damage,the heteroaggregation of MWCNTs-Cu O NPs and obvious nanoparticles internalization.In some groups,the presence of Cu O NPs significantly reduced reactive oxygen species(ROS)level induced by MWCNTs.However,for the highest concentration group,the ROS level was much higher than that of the two NPs alone treatment groups,which might be related to the high concentration of MWCNTs promoting the internalization of Cu O NPs.MWCNTs and Cu O NPs affected and interacted with each other,causing more complex toxic effects on aquatic organisms.展开更多
Conductive carbon nanotubes （CNTs） or alternatively polyaniline （PANI） nano-blocks was introduced into aqueous solutions of polyvinyl alcohol （PVA） and copper （II） salt, to assist the reduction of copper （II...Conductive carbon nanotubes （CNTs） or alternatively polyaniline （PANI） nano-blocks was introduced into aqueous solutions of polyvinyl alcohol （PVA） and copper （II） salt, to assist the reduction of copper （II） ions and the anchoring of the resulting copper nanoparticles onto the conductive blocks. The mixture solutions of nano-blocks, copper （lI） salts and PVA were spin-coated onto the cathode surface, forming swollen cathode films （SCFs）. The copper （II） ions in the film assembled onto the surfaces of the conductive blocks and were then reduced under an appropriate voltage. It is important that the copper nanoparticles grew only on the surfaces of the conductive blocks. PVA which acted as the matrix of the composites played a role in stabilizing the resulting copper nanoparticles. Morphologies of these polymeric composite films were studied by various characterization methods. Moreover, the mechanism of migration of copper （II） ions, the formation of these polymeric composites, and the overall procedure were investigated in detail.展开更多
基金This work was supported by the Doctoral Program of Higher Education of China （No.20110010110007） and the Beijing Municipal Natural Science Foundation （No.2102035）.
文摘In this work, we fabricated the polyaniline/silver nanoparticle/multi-walled carbon nanotube （PANI/Ag/MWCNT） composites by in situ polymerization of aniline on the wall of Ag/MWCNTs with different aniline to Ag/MWCNT mass ratios. The chemical structure of the ternary composites was characterized by Fourier transform infrared spectroscopy, Xray diffraction, and X-ray photoelectron spectroscopy. Scanning electron microscope and high-resolution transmission electron microscopy were used to observe the morphology of the ternary composites. The results showed that the polyaniline PANI layer was prepared successfully and it covered Ag/MWCNTs completely. In addition, Ag nanoparticles between the MWCNT core and the PANI layer existed in the form of elemental crystal, which could contribute to the electrochemical performance of the composites. Then we prepared the composite electrodes and studied their electrochemical behaviors in 1 mol/L KOH. It was found that these composite electrodes had very low impedance, and exhibited lower resistance, higher electrochemical activity, and better cyclic stability compared with pure PANI electrode. Particularly, when the mass ratio of aniline to Ag/MWCNTs was 5：5, the composite electrode displayed a small equivalent series resistance （0.23 Ω） and low interfacial charge transfer resistance （〈0.25 Ω）, as well as 160 F/g of the maximum specific capacitance at a current density of 0.25 A/g in KOH solution. We could conclude that the composite material had potential applications as cathode materials for lithium batteries and supercapacitors.
基金the financial support received from FRGS 1208/2013
文摘The thermal radiation energy is the clean energy with a much lower environmental impact than the conventional energy. The objective of the present work is to investigate theoretically the effect of copper nanoparticles and carbon nanotubes （CNTs） in the presence of base fluid （water） with the variable stream condition due to the thermal radiation energy. Single-walled carbon nanotubes （SWCNTs） in the presence of base fluid flow over a porous wedge play a significant role compared to those of copper nanoparticles on absorbing the incident solar radiation and transiting it to the working fluid by convection.
文摘Copper nanoparticles-decorated polyaniline- derived mesoporous carbon that can serve as noble metal-free electrocatalyst for the hydrazine oxidation reaction （HzOR） is synthesized via a facile synthetic route. The material exhibits excellent electrocatalytic activity toward HzOR with low overpotential and high current density. The material also remains stable during the electrocatalytic reaction for long time. Its good electro- catalytic performance makes this material a promising alternative to conventional noble metal-based catalysts （e.g., Pt） that are commonly used in HzOR-based fuel cells.
基金supported by the University of Engineering and Technology, Lahore, Pakistan
文摘The multiwalled carbon nanotubes thin-film-based electrode was fabricated by electrophoretic deposition and modified with copper （Cu） nanoparticles to fabricate Cu/CNTs nanocomposite sensor for nonenzymatic glucose detection. The expensive glassy carbon electrode was replaced by fluorine-doped tin oxide glass containing CNTs film to confine the Cu nanoparticles growth by electrodeposition through cyclic voltammetry （CV）. The ultraviolet visible and X-ray diffraction analysis revealed the successful deposition of Cu nanoparticles on the CNTs-modified electrode. The atomic force microscopy images confirrqed the morphology of electrodeposited Cu on CNTs film as uniformly dispersed particles. The electrocatalytic activity of electrode to the glucose oxidation was investigated in alkaline medium by CV and amperometric measurements. The fabricated sensor exhibited a fast response time of less than 5 s and the sensitivity of 314 μA rnM^-1 cm^-2 with linear concentration range （0.02-3.0 mM） having detection limit 10.0 μM. Due to simple preparation of sensor, Cu/CNTs nanocomposite electrodes are a suitable candidate for reliable determination of glucose with good stability.
文摘A novel hybrid material, Cu-PAA/MWCNTs （copper nanoparticles deposited multiwalled carbon nano- tubes with poly （acrylic acid） as dispersant, was prepared and expected to obtain a more effective and well-dispersed disinfection material for water treatment. X-ray energy dispersive spectroscopy （EDS）, transmission electron microscopy （TEM）, the X-ray fluorescence （XRF）, X-ray photoelectron spectra （XPS）, Fourier transform infrared spectra （FT-IR）, Raman spectroscopy, and thermal gravi- metric analyzer （TGA） were used to characterize the Cu- PAA/MWCNTs. Escherichia coli （E. coil） was employed as the target bacteria. The cell viability determination and fluorescence imaging results demonstrated that Cu-PAA/ MWCNTs possessed strong antimicrobial ability on E. coil. The deposited Cu was suggested to play an important role in the antimicrobial action of Cu-PAA/MWCNTs.
基金Funded by National Natural Science Foundation of China(Nos.51371129 and 11174226)Hubei Science and Technology Supported Project(No.YJG0261)+1 种基金Wuhan Science and Technology Research Project(No.2014010101010002)the Key Project of Guangdong Province(No.2013B090500078)
文摘Ag-Pt bimetallic nanoparticles decorated on MWCNTs/PANI nanocomposites have been synthesized by in-situ chemical oxidative polymerization and chemical co-reduction method. The Fourier transform infrared（FT-IR） spectroscopy, X-ray diffraction（XRD）, ultraviolet-visible（UV-vis） absorption spectroscopy, scanning electron microscopy（SEM） and transmission electron microscopy（TEM） were used to characterize the morphology and structure of the nanocomposites. It can be observed that the PANI was uniformly grown along the MWCNTs to form MWCNsT/PANI fiber-like nanocomposites with diameter about 60 nm, and the Ag-Pt binary nanoparticles were decorated onto MWCNTs/PANI with particle sizes around 6.8 nm. Cyclic voltammetry（CV） and electrochemical impedance spectroscopy（EIS） were used to characterize the electrochemical performance of the prepared electrode. The results demonstrated that the obtained MWCNTs/PANI/Ag-Pt electrode displayed a good electrochemical activity and fast electron transport, which has potential applications in biosensors and supercapacitors.
基金supported by the National Natural Science Foundation of China(Nos.51521006,51579095,51378190)Ecology and Environment Department of Hunan,the Program for Changjiang Scholars and Innovative Research Team in University(No.IRT-13R17)。
文摘Nanoparticles(NPs)are widely used for their special physical properties and released into the natural environment.When two types of NPs exist in the same environment,the presence of one type of NP may affect the properties of the other type of NP.This study investigated the toxic effects of multi-walled carbon nanotubes(MWCNTs)and copper oxide nanoparticles(Cu O NPs)on Tetradesmus obliquus.Both NPs had toxic effects on algae,and the toxic effects of MWCNTs were significantly stronger than Cu O NPs which the 96-hr median effective concentration to algae were 33.8 and 169.2 mg/L,respectively.Oxidative stress and cell membrane damage were the main reasons for the toxicity of NPs to algae,and they were concentration-dependent,and the existence of Cu O NPs in some groups reduced cell membrane damage caused by MWCNTs which may because that Cu O NPs formed heteroaggregation with MWCNTs,reducing the contact of nanoparticles with cell membranes,then reducing physical damage.Scanning electron microscopy(SEM)and transmission electron microscope(TEM)results indicated cell damage,the heteroaggregation of MWCNTs-Cu O NPs and obvious nanoparticles internalization.In some groups,the presence of Cu O NPs significantly reduced reactive oxygen species(ROS)level induced by MWCNTs.However,for the highest concentration group,the ROS level was much higher than that of the two NPs alone treatment groups,which might be related to the high concentration of MWCNTs promoting the internalization of Cu O NPs.MWCNTs and Cu O NPs affected and interacted with each other,causing more complex toxic effects on aquatic organisms.
基金NaturalScientific Foundation of China,grant No.51273096Shandong Province Project:tackle key problem in key technology,No.2010GGX10327)(2011 and 2012)+2 种基金Natural Scientific Foundation of Shandong Province through contract No.Y2008B06Program of Qingdao Science&Technology,Bureau to tackle key problem in key technology(2009-2011)International Collaborative Program of Qingdao Science&Technology Bureau,grant No.10-1-4-97-hz
文摘Conductive carbon nanotubes （CNTs） or alternatively polyaniline （PANI） nano-blocks was introduced into aqueous solutions of polyvinyl alcohol （PVA） and copper （II） salt, to assist the reduction of copper （II） ions and the anchoring of the resulting copper nanoparticles onto the conductive blocks. The mixture solutions of nano-blocks, copper （lI） salts and PVA were spin-coated onto the cathode surface, forming swollen cathode films （SCFs）. The copper （II） ions in the film assembled onto the surfaces of the conductive blocks and were then reduced under an appropriate voltage. It is important that the copper nanoparticles grew only on the surfaces of the conductive blocks. PVA which acted as the matrix of the composites played a role in stabilizing the resulting copper nanoparticles. Morphologies of these polymeric composite films were studied by various characterization methods. Moreover, the mechanism of migration of copper （II） ions, the formation of these polymeric composites, and the overall procedure were investigated in detail.
