The paper presents ac impedance behaviours of phenyl iso-thiocyanate adsorbed on Pt electrode.Nyquist plots are analysed and simulated,and parameters of relative equivalent circuits are obtained.
A photoelectrochemical process in the degradation of an azodye (Acid Orange II) on a Pt/TiO 2 film electrode was investigated. By using the glass device and the voltage stabilized source of direct current, decoloriza...A photoelectrochemical process in the degradation of an azodye (Acid Orange II) on a Pt/TiO 2 film electrode was investigated. By using the glass device and the voltage stabilized source of direct current, decolorization ratios higher than 78% were observed during a period of 5h. Comparing this value with the sum of the decolorization ratios obtained by a sole application of electrochemical(lower than 3%) and photochemical(about 23%) procedures, a significant synergic effect between both processes was observed. The effects of adscititious voltage and pH value on the decolorization ratios were obvious while the effect of the amount of aeration was minor.展开更多
The spillover phenomenon is observed on the platinum (Pt) disk electrode modified bymulti-wall carbon nanotubes (MWNTs). The rate of the spillover of oxygen-containing speciesproduced on Pt surface to and from MWNTs i...The spillover phenomenon is observed on the platinum (Pt) disk electrode modified bymulti-wall carbon nanotubes (MWNTs). The rate of the spillover of oxygen-containing speciesproduced on Pt surface to and from MWNTs is fast. However for hydrogen-adatoms, thespillover is very weak. The selective spillover on the Pt/MWNTs electrode may provide a novelway to design catalysts.展开更多
The processes of adsorption and oxidation of glycerol on Pt, Pt/Sbad and Pt/Sad electrodes were studied by using Cyclic voltammetry and electrochemical quartz crystal microbalance (EQCM). The results demonstrated that...The processes of adsorption and oxidation of glycerol on Pt, Pt/Sbad and Pt/Sad electrodes were studied by using Cyclic voltammetry and electrochemical quartz crystal microbalance (EQCM). The results demonstrated that the oxidation of glycerol depended strongly on oxidation states of electrode surface. Sb adatoms on Pt surface can adsorb oxygen at relatively low potentials, and exhibit catalytic effects for glycerol oxidation. In contrast to Pt electrodes, the oxidation peak potential of glycerol on Pt surface modified with Sb in saturation was negatively shifted by about 140 mV. In a contrary, the oxidation of S adatoms consumes oxygen species of Pt electrode surface. As a consequence, the oxidation of glycerol was inhibited on Pt surface modified with Sb in saturation. The EQCM studies provided quantitative results of surface mass variation during glycerol oxidation, and have thrown new light in elucidating different effects of adatoms Sbad and Sad on Pt electrode surface towards glycerol oxidation.展开更多
A simple and convenient electrochemical detection cell for capillary electrophoresis is described in this paper. In this cell, alignment of the capillary working electrode with the separation capillary outlet can be a...A simple and convenient electrochemical detection cell for capillary electrophoresis is described in this paper. In this cell, alignment of the capillary working electrode with the separation capillary outlet can be achieved precisely and easily without the aid of the micropositioner or microscope. With end-column detection, the applicability of the cell as an amperometric detector for capillary electrophoresis is demonstrated by running several phenolic compounds in 50 mu m i.d, capillary with a capillary Pt electrode as the working electrode. Results obtained are satisfactory.展开更多
文摘The paper presents ac impedance behaviours of phenyl iso-thiocyanate adsorbed on Pt electrode.Nyquist plots are analysed and simulated,and parameters of relative equivalent circuits are obtained.
文摘A photoelectrochemical process in the degradation of an azodye (Acid Orange II) on a Pt/TiO 2 film electrode was investigated. By using the glass device and the voltage stabilized source of direct current, decolorization ratios higher than 78% were observed during a period of 5h. Comparing this value with the sum of the decolorization ratios obtained by a sole application of electrochemical(lower than 3%) and photochemical(about 23%) procedures, a significant synergic effect between both processes was observed. The effects of adscititious voltage and pH value on the decolorization ratios were obvious while the effect of the amount of aeration was minor.
文摘The spillover phenomenon is observed on the platinum (Pt) disk electrode modified bymulti-wall carbon nanotubes (MWNTs). The rate of the spillover of oxygen-containing speciesproduced on Pt surface to and from MWNTs is fast. However for hydrogen-adatoms, thespillover is very weak. The selective spillover on the Pt/MWNTs electrode may provide a novelway to design catalysts.
文摘The processes of adsorption and oxidation of glycerol on Pt, Pt/Sbad and Pt/Sad electrodes were studied by using Cyclic voltammetry and electrochemical quartz crystal microbalance (EQCM). The results demonstrated that the oxidation of glycerol depended strongly on oxidation states of electrode surface. Sb adatoms on Pt surface can adsorb oxygen at relatively low potentials, and exhibit catalytic effects for glycerol oxidation. In contrast to Pt electrodes, the oxidation peak potential of glycerol on Pt surface modified with Sb in saturation was negatively shifted by about 140 mV. In a contrary, the oxidation of S adatoms consumes oxygen species of Pt electrode surface. As a consequence, the oxidation of glycerol was inhibited on Pt surface modified with Sb in saturation. The EQCM studies provided quantitative results of surface mass variation during glycerol oxidation, and have thrown new light in elucidating different effects of adatoms Sbad and Sad on Pt electrode surface towards glycerol oxidation.
文摘A simple and convenient electrochemical detection cell for capillary electrophoresis is described in this paper. In this cell, alignment of the capillary working electrode with the separation capillary outlet can be achieved precisely and easily without the aid of the micropositioner or microscope. With end-column detection, the applicability of the cell as an amperometric detector for capillary electrophoresis is demonstrated by running several phenolic compounds in 50 mu m i.d, capillary with a capillary Pt electrode as the working electrode. Results obtained are satisfactory.
