A cobalt nanoparticles-attached indium tin oxide（CoNPs/ITO） electrode was applied to the immobilization of hemoglobin（Hb） and an Hb modified CoNPs/ITO electrode（Hb/CoNPs/ITO） was prepared. The direct electron tr...A cobalt nanoparticles-attached indium tin oxide（CoNPs/ITO） electrode was applied to the immobilization of hemoglobin（Hb） and an Hb modified CoNPs/ITO electrode（Hb/CoNPs/ITO） was prepared. The direct electron transfer of Hb was shown by the well-behaved voltammetric responses for Hb/CoNPs/ITO electrode and the effects of scan rate and pH value were observed. Based on the catalytic activity of Hb immobilized on the CoNPs/ITO electrode toward the reduction of H2O2, a mediator-free H2O2 sensor was developed. A linear relationship existed between the catalytic current and the H2O2 concentration in a range of 1.0--100.0 μmol/L with a detection limit （S/N=3） of 0.2μmol/L.展开更多
The electrocatalytic oxidation of nitric oxide（NO） at a glass carbon electrode（GC） modified with functionalized single-walled carbon nanotubes（SWCNTs） was investigated by cyclic voltammetry（CV） and electrochem...The electrocatalytic oxidation of nitric oxide（NO） at a glass carbon electrode（GC） modified with functionalized single-walled carbon nanotubes（SWCNTs） was investigated by cyclic voltammetry（CV） and electrochemical impedance spectroscopy（EIS）.It was found that the SWCNT modified electrode could speed greatly up the electron transfer rate compared with the bare GC electrode.After the SWCNT was treated with alkali or mixed acids,the reaction rate and activation energy of NO electrooxidation were changed to different extent.Chemical modification of the SWCNT surface is one of the most powerful methods to change the sensitivity of NO electrooxidation reaction.The modified electrode with SWCNT obtained by the firstly alkali treatment and then the mixed acids treatment was the best one for NO electrooxidation,the result of CV was also confirmed by that of EIS.The anodic processes of NO were recognized more clearly by exploring the reaction mechanism of NO electrooxidation at the SWCNT modified electrode.展开更多
The electrocatalytic oxidation of contraflam was investigated in alkaline solution on nickel and nickel–copper alloy modified glassy carbon electrodes(GC/Ni and GC/NiCu). We prepared these electrodes by galvanostatic...The electrocatalytic oxidation of contraflam was investigated in alkaline solution on nickel and nickel–copper alloy modified glassy carbon electrodes(GC/Ni and GC/NiCu). We prepared these electrodes by galvanostatic deposition and the surface morphologies and compositions of electrodes were determined by energy-dispersive X-ray(EDX) and scanning electron microscopy(SEM). Cyclic voltammetry and chronoamperometric methods were employed to characterize the oxidation process and its kinetics. Voltammetric studies exhibit one pair of well-defined redox peaks, which is ascribed to the redox process of the nickel and followed by the greatly enhanced current response of the anodic peak in the presence of contraflam and a decrease in the corresponding cathodic current peak. This indicates that the immobilized redox mediator on the electrode surface was oxidized contraflam via an electrocatalytic mechanism. The catalytic currents increased linearly with the concentration of contraflam in the range of 0.25– 1.5 mmol/L. The anodic peak currents were linearly proportional to the square root of scan rate. This behaviour is the characteristic of a diffusion-controlled process. The determination of contraflam in capsules is applied satisfactorily by modified electrode.展开更多
The electro-oxidation of formaldehyde on a gold electrode in a gold electrode in a solution containing0.1mol ·L -1 Na2 CO3＋0. 1mol·L - 1NaHCO3＋0. 1 mol·L, - 1 HCHO was investigated bycyclic voltammetr...The electro-oxidation of formaldehyde on a gold electrode in a gold electrode in a solution containing0.1mol ·L -1 Na2 CO3＋0. 1mol·L - 1NaHCO3＋0. 1 mol·L, - 1 HCHO was investigated bycyclic voltammetry and in -situ FTIR spetroscopy . The experimental results demonstrated that the oxidation of formaldehyde at different potential range connected with different surface species of gold. At lower potentials, the main product of formaldehyde oxidationwas HCOO-, and at higher potentials, the products HCOO- and CO2 were detected simultaneously. From the results, a possible reaction mechanism was proposed.展开更多
以苯胺(ANi)为单体,过硫酸铵(APS)为氧化剂,氧化石墨烯(GO)为模板,调节ANi与GO原料质量比从0.5到100,采用原位聚合法制备了一系列不同组分含量的聚苯胺/氧化石墨烯(PANi/GO)复合材料。采用傅里叶变换红外光谱、X射线衍射谱、扫描电镜和...以苯胺(ANi)为单体,过硫酸铵(APS)为氧化剂,氧化石墨烯(GO)为模板,调节ANi与GO原料质量比从0.5到100,采用原位聚合法制备了一系列不同组分含量的聚苯胺/氧化石墨烯(PANi/GO)复合材料。采用傅里叶变换红外光谱、X射线衍射谱、扫描电镜和循环伏安法对制备复合材料的结构、微观形貌和循环伏安性能进行了研究,着重考察了原料配比对PANi/GO复合材料结构、微观形貌及能量存储的影响。研究表明:ANi单体成功原位聚合在GO表面上;ANi/GO质量比对PANi/GO复合材料的比电容影响明显;随着ANi/GO质量比的增加,所制备复合材料的比电容先增加后减小。当ANi/GO质量比为10、扫描速率为10 m V·s^(–1)时,复合材料的比电容达到最大值162.2 F·g^(–1)。展开更多
基金Supported by the National Natural Science Foundation of China（No.20211130505） and the Fundamental Research Funds for the Central Universities of China.
文摘A cobalt nanoparticles-attached indium tin oxide（CoNPs/ITO） electrode was applied to the immobilization of hemoglobin（Hb） and an Hb modified CoNPs/ITO electrode（Hb/CoNPs/ITO） was prepared. The direct electron transfer of Hb was shown by the well-behaved voltammetric responses for Hb/CoNPs/ITO electrode and the effects of scan rate and pH value were observed. Based on the catalytic activity of Hb immobilized on the CoNPs/ITO electrode toward the reduction of H2O2, a mediator-free H2O2 sensor was developed. A linear relationship existed between the catalytic current and the H2O2 concentration in a range of 1.0--100.0 μmol/L with a detection limit （S/N=3） of 0.2μmol/L.
基金Supported by the National Natural Science Foundation of China(Nos.20676027 and 21076066)the Postdoctoral Foundation of Heilongjiang Province,China(No.LBH-Q07111)
文摘The electrocatalytic oxidation of nitric oxide（NO） at a glass carbon electrode（GC） modified with functionalized single-walled carbon nanotubes（SWCNTs） was investigated by cyclic voltammetry（CV） and electrochemical impedance spectroscopy（EIS）.It was found that the SWCNT modified electrode could speed greatly up the electron transfer rate compared with the bare GC electrode.After the SWCNT was treated with alkali or mixed acids,the reaction rate and activation energy of NO electrooxidation were changed to different extent.Chemical modification of the SWCNT surface is one of the most powerful methods to change the sensitivity of NO electrooxidation reaction.The modified electrode with SWCNT obtained by the firstly alkali treatment and then the mixed acids treatment was the best one for NO electrooxidation,the result of CV was also confirmed by that of EIS.The anodic processes of NO were recognized more clearly by exploring the reaction mechanism of NO electrooxidation at the SWCNT modified electrode.
基金financial assistance from Tehran University of Medical Sciences,Tehran,Iran
文摘The electrocatalytic oxidation of contraflam was investigated in alkaline solution on nickel and nickel–copper alloy modified glassy carbon electrodes(GC/Ni and GC/NiCu). We prepared these electrodes by galvanostatic deposition and the surface morphologies and compositions of electrodes were determined by energy-dispersive X-ray(EDX) and scanning electron microscopy(SEM). Cyclic voltammetry and chronoamperometric methods were employed to characterize the oxidation process and its kinetics. Voltammetric studies exhibit one pair of well-defined redox peaks, which is ascribed to the redox process of the nickel and followed by the greatly enhanced current response of the anodic peak in the presence of contraflam and a decrease in the corresponding cathodic current peak. This indicates that the immobilized redox mediator on the electrode surface was oxidized contraflam via an electrocatalytic mechanism. The catalytic currents increased linearly with the concentration of contraflam in the range of 0.25– 1.5 mmol/L. The anodic peak currents were linearly proportional to the square root of scan rate. This behaviour is the characteristic of a diffusion-controlled process. The determination of contraflam in capsules is applied satisfactorily by modified electrode.
文摘The electro-oxidation of formaldehyde on a gold electrode in a gold electrode in a solution containing0.1mol ·L -1 Na2 CO3＋0. 1mol·L - 1NaHCO3＋0. 1 mol·L, - 1 HCHO was investigated bycyclic voltammetry and in -situ FTIR spetroscopy . The experimental results demonstrated that the oxidation of formaldehyde at different potential range connected with different surface species of gold. At lower potentials, the main product of formaldehyde oxidationwas HCOO-, and at higher potentials, the products HCOO- and CO2 were detected simultaneously. From the results, a possible reaction mechanism was proposed.
文摘以苯胺(ANi)为单体,过硫酸铵(APS)为氧化剂,氧化石墨烯(GO)为模板,调节ANi与GO原料质量比从0.5到100,采用原位聚合法制备了一系列不同组分含量的聚苯胺/氧化石墨烯(PANi/GO)复合材料。采用傅里叶变换红外光谱、X射线衍射谱、扫描电镜和循环伏安法对制备复合材料的结构、微观形貌和循环伏安性能进行了研究,着重考察了原料配比对PANi/GO复合材料结构、微观形貌及能量存储的影响。研究表明:ANi单体成功原位聚合在GO表面上;ANi/GO质量比对PANi/GO复合材料的比电容影响明显;随着ANi/GO质量比的增加,所制备复合材料的比电容先增加后减小。当ANi/GO质量比为10、扫描速率为10 m V·s^(–1)时,复合材料的比电容达到最大值162.2 F·g^(–1)。
