SU824005A2 - Liquce metal electrical measuring device - Google Patents

Description

(54) THE DEVICE FOR ELECTROCHEMICAL MEASUREMENTS ON LIFE METALS 3 does not allow to radiate the kinetics of the electrode processes. The purpose of the invention is the expansion of the device's functional capabilities. The goal is achieved by the fact that a device for electrochemical measurement on liquid metals is made from an i-shaped tube with a partition, which has a capillary hole in the center dividing the cell volume into two compartments in which liquid measuring electrodes are located that cover the capillary hole, where the ratio of the thickness of the septum to the diameter of the capillary orifice is (within 1.0 0.2, where 1 is the bulkhead of the septum, the d-diameter of the capillary orifice contains a supply current collector dop 1 piece liquid electrode, A channel is located perpendicular to the channel of the capillary orifice and connected to it in the partition. The drawing shows the device, its appearance. The device contains a glass cell I, in which two liquid electrons of the line 2 with platinum current leads 3 are separated by a subroads 4 (thickness 0.05 cm), with a cass opening 5 (with a diameter of 0.026 cm). In the wall of the I1 partition, there is a large cough measuring electrode 6 with a CLOSED 7, located in a channel perpendicular to the channel of the capillary opening, receiving the surface electrode is at a level surface Nogo capillary holes 5, i.e. channels are connected. With the whole exclusion of the influence of the working electrode on the geometry of the capillary hole, its diameter (20 microns) is not less than an order of magnitude smaller than the diameter of the capillary hole. Electrical measuring circuit from coentiostat 8 with self-recording device 9 to it and two voltmeters 10 and M, the inputs of which are connected to recorders 12 and 13. When preparing the device for electrochemical measurements, capillary hole 5 is filled with electrolyte under test, then metallic mercury is placed in the compartments of the cell which bridges the capillary hole with electrolyte, forming a mercury – capillary micrrh cell. A liquid capillary electrode 6 is formed (electrochemically 05 by cathode deposition of metallic mercury on a platinum current lead 7, and one or both working electrodes 2 are used as an anode. Measurements are performed using a potentiostat 8 on a working electrode 2 (voltage) at a speed of 0.5 v / h. With the help of the recorder 13, the value of the working current flowing through the device between the electrodes 2 is recorded. With the help of voltmeters 10 and 11 and the recorders I2 and 13 are recorded with responsibly, the cathode and anode overvoltage of mercury working electrodes 2 relative to the equilibrium nonprizable mercury electrode 6 in the same solution ... depending on the magnitude of the applied voltage to the cell. The device allows dividing the applied voltage of the cell into its components, estimating the complete picture of the voltage distribution in whose ke, the nature of the resulting, anodic and cathodic polar; characteristics allows one to judge the kinetics of electrode processes and the mechanism of mercury transfer in a microcell. When using mercury electrolyte composition 1n HgJj 5nK7 approximately 20-30% of the attached; . the voltage is applied (falls) on the cathode discharge process, of mercury ions, and the rest on the ionization process of mercury (80-70%). At high currents (above 300 μA). the phenomenon of passivation of the anode occurs due to the deposition of an insoluble film on its surface, and the voltage increases and the current remains constant, since the rate of mercury transfer is determined by the rate of chemical dissolution of the film. All applied voltage falls at the anode. The results of these studies allow the development of optimal constructions and sausages of electrolytes for mercury capillary electrochemical converters, as well as being of theoretical interest. The known device does not allow splitting the applied voltage into its components, therefore its functions are limited by measuring,

rhenium of electrical conductivity and ordinary current-voltage curves.

Thus, the introduction of an additional liquid capillary comparison electrode into the measuring part of the cell expands the functionality of the device. In addition to measuring the electrical conductivity and removing current-voltage curves (the voltage across the cells), the device allows you to measure

: anodic and cathodic polarization characteristics, which are unsuitable for the study and development of electrolytes for molecular electronic transducers, as well as the kinetics of electrode liquid: metals and amalgams. This expands the volume of electrically explored liquid metal research. In addition to the polarization characteristics, the device allows conducting imidance and potentiodynamic studies of anodic and cathodic processes occurring on liquid metals. The cell, unlike limestone, uses e1 & 1x for electrochemical cells on liquid metals (rotating droplets, disk rotating electrodes, etc.) has the following advantages:

1. It provides a strictly constant value of the surface area of the test of the surface of mercury electrons and the distance between them, which may

to be extremely small, which is important when studying the kinetics of fast electrochemical reactions (the voltage drop across the resistance of the electrolyte is practically eliminated).

2. Provides a higher rate of electrolyte mixing due to the “general” movements of the surface layers of mercury, which provides a high current density,::; V,,; .....

Claims (1)

1. USSR author's certificate No. 748217, cl. G 01 N 27/02, 1978 (prototype).