Method for preparing hydrogen electrode composite powder of solid oxide electrolyzer

Abstract

The invention relates to a method for preparing hydrogen electrode composite powder of a solid oxide electrolyzer, belonging to the field of high-temperature steam electrolysis hydrogen preparation and solid oxide electrolyzer. The preparation method comprises the steps of: with nickel nitrate, YSZ (Yttria Stabilized Zirconia) powder and urea as raw materials, controlling reaction conditions of the addition of the urea, the hydrolysis temperature of the urea and ultrasonic time when the powder is prepared, depositing NiO on a YSZ particle through two-step reactions of homogeneous precipitation and low-temperature spontaneous combustion, and finally preparing the NiO-YSZ hydrogen electrode composite powder of the solid oxide electrolyzer through roasting, wherein the nickel nitrate is used as a nickel source, the YSZ powder is used as a core of a composite powder and the urea is a settling agent in a uniform settling process and a combustion improver in a combustion process. The NiO-YSZ composite powder prepared by using the method has the advantages of good adhering property of two phases of NiO and YSZ, uniform dispersing, accurate stoichiometric proportion, strong catalytic activity, high utilization ratio of the nickel, and the like. The invention is suitable for preparing the NiO-YSZ hydrogen electrode composite powder of the solid oxide electrolyzer.

Description

technical field [0001] The invention belongs to the field of hydrogen production by high-temperature steam electrolysis, and in particular relates to a preparation method of a hydrogen electrode composite powder of a solid oxide electrolytic cell. Background technique [0002] Solid oxide electrolysis cell (Solid oxide electrolysis cell, SOEC) is an energy conversion device that converts electrical energy and thermal energy into chemical energy. the reverse process. The hydrogen production efficiency of using SOEC to electrolyze water vapor at high temperature can be as high as 45-59% (hydrogen production efficiency is defined as the ratio of the energy content of produced hydrogen to the energy used for hydrogen production), which is a potential large-scale hydrogen production method one. However, in order to achieve commercial mass production of this technology, in addition to solving problems such as the coupling between the hydrogen production unit and the reactor, for...

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Problems solved by technology

However, in order to ensure that the particles of NiO are fine in this invention, the deposition reaction of nickel needs to be carried out at a higher degree of supersaturation, and when the pH value of the solution is too high, ammonia water will complex with nickel ions to produce Ni(NH 3 ) 6 2+ , so that the precipitated Ni(OH) 2 Dissolution reduces the yield of NiO, and also makes it difficult to accurately control the mass ratio of NiO and YSZ in the composite powder

In addition, due to the uneven concentration of substances in the solution and the rapid formation of precipitation in the commonly used precipitation process of adding a precipitant, it is easy to cause a wide particle size distribution of the precipitated particles.

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