Ag/agf reference electrode suitable for fluoride molten salt and preparation method thereof

Abstract

The invention provides an Ag / AgF reference electrode suitable for fluoride molten salt and its preparation method, which includes a corundum tube, a film arranged at the sealing end of the corundum tube, a sealing plug arranged at the opening end of the corundum tube, and an internal reference electrode arranged in the corundum tube Salt is also provided with a silver wire, the silver wire passes through the piston and is immersed in the internal reference salt, and the silver wire is connected to the anode of the power supply. The present invention proposes a corundum tube as the diaphragm material and Ag / AgF reference electrode and preparation method thereof, the reference electrode has good stability, good reversibility, simple structure and low price; the Ag / AgF reference electrode of the present invention is simple in structure, strong and durable, good in stability and good in reversibility , good reproducibility, long service life, suitable for various fluoride molten salt systems below 700 degrees Celsius.

Description

technical field [0001] The invention relates to an Ag / AgF reference electrode and a preparation method thereof, in particular to an Ag / AgF reference electrode suitable for fluoride molten salts and a preparation method thereof. Background technique [0002] Fluoride molten salt has a series of advantages such as good high temperature stability, high thermal conductivity, large specific heat capacity, wide electrochemical window, low saturated vapor pressure and small neutron absorption cross section. , surface treatment technology, electronic chemicals, fine chemicals, and molten salt battery materials are widely used, especially in nuclear reactor coolants, molten salt electrolytes, high-temperature energy storage materials, and reaction media. However, due to the high temperature and strong corrosion of fluoride molten salts, there is still a lack of suitable high-temperature fluoride salt reference electrodes at home and abroad, which greatly restricts the application and...

AI Technical Summary

Problems solved by technology

However, due to the high temperature and strong corrosion of fluoride molten salts, there is still a lack of suitable high-temperature fluoride salt reference electrodes at home and abroad, which greatly restricts the application and research of high-temperature fluoride salts.

[0003] The reference electrodes commonly used in fluoride salts are quasi-reference electrodes: such as Pt, W, Mo, etc., but they do not have exact redox pairs in molten salts, and the electrode potential is easily affected by changes in the molten salt system; another Ni / NiF 2 Reference electrode: Oak Ridge Laboratory in the United States designed Ni / NiF with solid lanthanum trifluoride as the diaphragm material 2 Reference electrode, but lanthanum trifluoride is easily soluble in fluorine salts, and LaF 3 Single crystals are prone to cracking; Greece's Kontoyannis uses graphite (EK-90) as Ni / NiF 2 The diaphragm material of the reference electrode, but graphite is easily dissolved in high-temperature molten salt, and at the same time, the contact between nickel wire and graphite produces a conductive circuit, which has a short service life; patent ZLCN201410158185.9 discloses a Ni / NiF that uses an insulating sleeve as the diaphragm material 2 Reference electrode, in which ion conduction is achieved by opening holes, but the opening of the holes easily leads to material exchange between the inner and outer molten salts, which affects the stability of the reference electrode; patent ZLCN201410854193.7 improves Ni / NiF with graphite as the diaphragm material 2 For the reference electrode, a pyrolytic boron nitride sleeve is added inside the graphite, and a pyrolytic boron nitride coating is attached to the outside of the graphite, which solves the problems of easy cracking of graphite in high temperature environment and the service life of the reference. However, the preparation process is complicated and the cost is high

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