SU1459419A1 - Method for making sensitive element of hydrogen sensor - Google Patents

Abstract

The invention for analytic and analytical instrumentation is possible to be used for the fabrication of sensors for the determination of hydrogen in gas mixtures and makes it possible to obtain a sensor with high sensitivity, fast performance and stability of operation. The purpose of the invention is to increase the sensitivity, speed and stability of the dachz operation. The method of manufacturing the hydrogen sensor element consists in sequentially placing the mold of the powders of the solid electrolyte electrode and the electrode. Zirconium hydrogen phosphate is used as the solid electrolyte. Pressing is carried out at a pressure of 9000-10000 kg / cm. Heat treatment of solid electrolyte is carried out at a temperature of 500-600 ° C for 2-3 hours, followed by treatment in pairs of sulfuric acid at a temperature of 90-12Q ° C for 15-24 hours and cyvic in air flow.

Description

one

The present invention relates to x7-III III and analytical instrumentation, and specifically to methods for producing sensors for determining hydrogen in gas mixtures,

The aim of the invention is to increase the sensitivity, speed and stability of the resulting sensor,

Example. A portion of zirconium hydrogen phosphate, doped with gddroxy-lithium, 0.3 g is placed, a tablet with a diameter of 0-13 mm is pressed into the mold and under a slight pressure of 200 kg / s. Then, both surfactants of JOSLE, THRESHOLDLY BEHEAL

a layer of platinum or palladium powder is applied. Next, the sample is pressed at a pressure of 10,000 kg / cm in the following sequence: load the tablet for 1-3 minutes, hold it under pressure at 15g 20 min and gradually release pressure in a calculation of 2-3 tons / min. After pressing, the sensor is placed in an oven and held at 600 ° C for 2 hours. After heat treatment, the sensor is held in sulfuric acid vapor of 0.1 M for 24 hours at 100 ° C.

After processing, the fabricated sensor is dried for 6-10 hours in a stream of air at room temperature (drying in a stream is allowed at 40 p a (D

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50 C 5 at the same time drying time can be reduced to 2-3 hours).

As a result, a Neither sensor based on the technology used was used, which has an output sensitivity of A 5 MB with a sample volume of j ml and kon-. Criteria for Hj in Sample 10 | fast rotated on the leading edge of 1j5 s, the total duration of the signal 35 s at a speed of air flow through the sensor 50 Ml / min

When used for 3 months at room temperature O) The change in sensitivity did not exceed 15%,

When pressures are less than 5000 kg / cm 1, the sensitivity of the sensors shrinks at pressures higher than 10,000 kg / cm 5 the deformation of the mold leads to the destruction of the sensor when it is removed from the mold.

With a decrease in temperature, heat treatment below 500 ° C, the sensitivity of the sensor increases, however, this significantly deteriorates the stability of the work-in time. With an increase in heat treatment temperature, the operation of the sensor improves, but at temperatures higher than 600 ° C, the sensitivity of the sensor decreases. Thus, the manufacture of the sensor at yica-znps temperatures is optimal from the point of view of stability while maintaining the maximum possible

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At times less than 2 hours, the sensitivity of datasr rv decreases as the complete formation of a solid electrolyte phase does not occur after 3 hours of heat treatment. Further changes in the properties of the electrolyte do not go away, therefore an increase in heat treatment time is not rational.

as concerns the processing of the sensor in sulfuric acid vapor, it is preferable to treat the tablet in pairs of 0.1-0.4 acid at 90-120 ° C for 15-24 hours,

The decrease in concentration leads to a significant increase in the required treatment in pairs. An increase in the concentration leads to a decrease in the partial pressure of steam / at 100 ° Cj, which also results .; Increased processing time.

The data produced by this method has a linear dependence of the amplitude and signal amplitude on the concentration of hydrogen in air and other gases (He, Ar, N) - in the range, 0% by volume. Measurement time 30-45 sec. Limit of detection of hydrogen in air in volume, -,:

Formula of O b r e s s n and I

A method of manufacturing a hydrogen sensor element, comprising sequentially placing electrode powders in a mold,. solid electrolyte and electrode, followed by pressing about t l and. Due to the fact that in order to improve the sensitivity, speed and stability of the sensor obtained as a solid electrolyte, lithium-doped zirconium hydrogen phosphate is used, the pressing is carried out at a pressure of; 9000 to 10000 kg / cm; in addition, a sequential thermal treatment is additionally carried out: 5 processing of the obtained tablet; at a temperature of from 500 to 600 ° C for a time, from 2 to 3 hours and its processing in vapors of sulfuric acid at a temperature of from 90 to 20 s for: time from 15 to 24 hours; ;

Claims (1)

A method of manufacturing a hydrogen sensor element comprising sequential placement of c. mold powder electrodes. solid electrolyte and electrode, followed by pressing, about t l and -. characterized in that, in order to increase the sensitivity, speed and stability of the obtained sensor, lithium doped zirconium phosphate is used as a solid / 35th electrolyte, pressing is carried out at a pressure of; 9000 to 10000 kg / cm ⁴ , additionally conduct sequential thermal-1: processing of the obtained tablet · at a temperature of from 500 to 600 C over time, from 2 to 3 hours and processing it in sulfuric acid vapors at a temperature of from 90 to 120 C over a period of 15 to 24 hours,.