Product introduction:
Body material: PTFE
Window material: quartz
Common volume: 50-250ml
Sealing method: external thread sealing, 360 degree rotation, making the electrode correspond to the light window Features:
1 can be a single layer, can pass into the air.
2. The reference electrode and the working electrode are in the same chamber, which effectively reduces the R drop.
3. Intermediate isolation with proton exchange membrane
4. The left and right sides can be customized
5 can increase the valve (with the use of chromatography) How to choose electrochemical reaction electrolytic cell
Taking oxygen reduction as an example, the oxygen reduction reaction (ORR) is
The main reaction of the battery air cathode, used to evaluate the performance of the catalyst, has been studied by many researchers.
extensive attention. The electrolytic cell is an indispensable part of the experimental process and measures electrochemical
Trial effects also have an impact, which is often overlooked by many researchers. How to choose the right electrolysis
Pool is particularly important.
The main factors affecting the electrochemical reaction in the electrolytic cell:
1. The volume of the electrolytic cell, the oxygen reduction reaction (ORR) needs to provide a good liquid laminar flow state,
Thereby obtaining a uniform current distribution. From the analysis of the liquid phase mass transfer process, the dissolution away from the electrode surface
In the liquid, convection is the main mass transfer process, and the mass transfer in the solution layer near the electrode surface is mainly dependent on the
By diffusion process. However, it is very difficult to distinguish the two mass transfer processes strictly in general.
There is always a region of space where the two mass transfer methods interact. Therefore, in order to eliminate both
The influence of the shift can separate the diffusion mass transfer zone and the convection mass transfer zone, requiring a relatively small volume of electrolyte.
Large, thus requiring a large volume electrolytic cell. When the rotating disk electrode rotates, it can be thought of as
The electrolyte concentration at each position in the bath is uniform. At the same time, choose a larger electrolytic cell and rotate
The disk electrode is far enough away from the cell wall of the electrolysis cell and the flow and movement of the electrode is not affected by the cell wall, often
It is advisable to use an electrolytic cell volume of 150 mL, and if the volume is too small (eg 50-100 mL), the result of the experiment will be
Adversely affected.
2. The geometry of the electrolytic cell and the equivalent circuit of the electrochemical cell are shown in Fig. 1. Ru is a worker.
As the resistance between the electrode and the reference electrode solution, the smaller the distance between the working electrode and the reference electrode, the greater the resistance
Small, Piontelli has systematically studied the effect of the reference electrode placement on the electrochemical test results.
It shows that when the reference electrode is directly below the working electrode and the open top of the reference electrode is close to the operating power
At the extreme, the test is best. However, the design of this placement is not practical in the actual operation.
Because when the rotating disk's working electrode rotates, it will generate friction with the reference electrode, which will result in laminar flow.
The state caused great disturbances. Barnartt study shows that when the distance between the working electrode and the end of the reference electrode is
The test effect is best when it is four times the radius of the electrode (ie about 5mm). At this distance, due to electrolysis
The low conductivity of the material or the IR drop produced at high current densities can be corrected. Current electrolytic cell often
As seen in Figure 2, the electrolytic cell not only satisfies the larger volume (150 mL) of the electrolytic cell,
At the same time, its geometry also satisfies the most suitable distance between the working electrode and the reference electrode (fixed socket position),
This reduces the effect of the internal resistance of the solution on the experimental results.
In summary, during the oxygen reduction reaction (ORR) process, at least the choice of electrolytic cell needs to be considered.
Its volume and geometry are two aspects. Other electrochemical reactions such as OER, hydrogen evolution
It should also follow this principle.
Product introduction:
Body material: PTFE
Window material: quartz
Common volume: 50-250ml
Sealing method: external thread sealing, 360 degree rotation, making the electrode correspond to the light window
