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Ultrasound electrochemical process

Author: FuXiangLin
Tutor: XuWenLin；WangYaQiong
School: Yangzhou University
Course: Applied Chemistry
Keywords: Ultrasonic frequency Ultrasonic power Oxygen precipitates Electrodeposition Mass transfer
CLC: O646
Type: Master's thesis
Year: 2005
Downloads: 319
Quote: 2
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Abstract

In this paper, the electrochemical reaction process research system, ultrasonic gas generation process, the typical process of the mass transfer process and cathode deposition process. In this study, the main features of performance systematically study the influence of ultrasonic gas generation process, the mass transfer process and electrodeposition process, quantitative ultrasonic output frequency, ultrasonic output power and temperature of the reaction system as well as explore the different temperature The effect of the ultrasonic field. Investigated by ultrasonic acoustic parameters typical electrochemical process of electrochemical process, providing technical parameters and theoretical guidance for the application of ultrasound in the electrochemical process. An ultrasonic water electrolysis anode put the oxygen process electrolytic 1.0mol/LKOH aqueous solution as a research system, a three-electrode system, the working electrode for nickel electrode, auxiliary electrode was a stainless steel electrode and reference electrode was a saturated calomel electrode, respectively. determined by ultrasound and no ultrasound anode of the electrolysis of aqueous KOH solution steady-state polarization curves at different temperatures, ultrasound anode discharge current density of the oxygen process potentiostat operating conditions, the oxygen yield and current efficiency. The results show that: ultrasound have a significant impact on the anodic process. Current density in the current density when the ultrasound is greater than the current density when ultrasound at the same temperature and the same electrode potential, at a temperature of 25 ° C, when the electrode potential of 0.500 (vs.SCE), the ultrasonic is 1.27 times the current density ultrasound. The generation amount of oxygen when the oxygen generated when the ultrasonic greater than the amount of oxygen generated when no ultrasound, ultrasound and the ratio of the amount of oxygen when no ultrasound is reduced as the temperature rises in the electrode potential of 1.000 V (vs.SCE), the temperature was elevated from 25 ℃ to 55 ℃, the the ultrasonic when the amount of oxygen and the ratio of the amount of oxygen when no ultrasound is decreased from 1.37 to 1.20. Ultrasound and without ultrasound, current efficiency when the role of the current efficiency and without ultrasound in the ultrasound are increased as the temperature increases, the temperature was raised to 55 ° C from 25 ℃ the current efficiency were increased from 96.7% to 99.1% and from 90.6% to 98.6%. 2. Ultrasound ferricyanide restore the reaction rate of the potassium ferrocyanide at the working electrode and the auxiliary electrode are platinum electrode, the reference electrode was a saturated calomel electrode of the three electrode system, in alkaline medium ferricyanide potassium to restore the the potassium ferrocyanide research system, respectively in ultrasound and Yangzhou University, a master's degree thesis ultrasound, determination of the reaction temperature and reactant concentration down to earth Fe (CN) 6 electrochemical reduction process current density on the steady-state polarization curves. The results show that: where Fe (CN) 6 electrochemical reduction process, the ultrasound can significantly increase the response speed of the process and the diffusion limiting current density, and ultrasound on the mass transfer controlled limiting current density greater than non the degree of influence of the current density of the mass transfer controlled region Where the concentration of Fe (CN) 6 0.04m. Long, in the electrode potential of 0.15V (vs.ScE), the current density of the ultrasound is no ultrasound 26.0 times, when the electrode potential when a 0.3OV (SCE), the ultrasound limits The current density was 65.0 times the limiting current density in the ultrasound. When the temperature from 25 ℃ to 65 ℃, ultrasound and non-ultrasound limiting diffusion current density ratio reduced from 68.4 to 54.0. As the temperature increases, the cavitation effect is weakened. The role of the ultrasound and no ultrasound limiting diffusion current density with increasing concentrations of the reactants increases, basically a linear relationship with the concentration of reactants. 3. Ultrasound copper electrochemical deposition process to CuSO4 a play 504 for the research system, a three-electrode system, and copper as the working electrode, platinum electrode as the reference electrode, a saturated calomel electrode as auxiliary electrode, in constant ultrasonic power and frequency, ultrasound and no ultrasound, copper electrochemical deposition process cathodic polarization curves, discussed the impact of ultrasound on the crystal plane orientation and surface morphology of the electrodeposited copper were measured. The results show that: introducing the ultrasound through the polarization curves in a copper electrochemical deposition process can be shown that the ultrasound can be significantly improved copper electrodeposition cathode of the diffusion limiting current density, and as the temperature increases, the weakening of the ultrasonic cavitation. 25 ℃, the mean limiting current density when the ultrasonic to 73.3A angle 12, when the mean limiting current density without ultrasound 5.2A/mZ temperature was increased to 55 ° C from 25 ℃ ultrasound limit when the current density and the ratio of the limiting current density ultrasound decreased from 14.1 to 8.4. By X-ray diffraction analysis showed that the copper deposited layer under ultrasonication diffraction the Fengfeng strength higher than without ultrasound diffraction peak-to-peak intensity, the introduction of ultrasound and in certain electrolysis conditions can make the copper electrodeposition of the crystal face orientation change. 30 ℃ and 400 A / mZ conditions electrolysis time of 30 min, ultrasound Cu (200) crystal plane orientation significantly increased; ultrasound introduction of copper electrochemical deposition process can also promote the formation of nuclei, while crack normal Development of crystal, so that the particle diameter of the electrically deposited copper change significantly. When the electrochemical reaction is carried out in the ultrasonic field, the power and frequency of the ultrasound is important parameters that affect the ultrasonic effects. Different ultrasonic output power, the copper electrochemical deposition Cheng Fuan curve results show that: the present experimental conditions, ultrasonic frequency 24kHz, when the ultrasound output power is small, the introduction of ultrasound can significantly

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