A ca-w mixed doping bi 2 o 3 Preparation method of solid electrolyte

Abstract

A Ca‑W mixed doped Bi 2 o 3 A method for preparing a solid electrolyte relates to the technical field of solid electrolyte preparation. First Ca(NO 3 ) 2 , (NH 4 ) 10 W 12 o 41 ·xH 2 O, Bi(NO 3 ) 3 Dissolve with distilled water; then add citric acid and adjust the pH value of the system, then use an ultrasonic cleaner to disperse evenly, and then transfer to a microwave chemical reactor to heat and react to form a wet gel; finally, the wet gel is dried, calcined, and then pelletized and sintered. Ca x Bi 1.7‑x W 0.3 o 3.45‑0.5x Fluorite crystal structure can be obtained by pre-sintering at 760°C, and sintered at 780°C for 2 hours, a dense ceramic sintered body with a relative density higher than 97% can be obtained, and the electrical conductivity can reach 0.07978S cm at 750°C ‑1 , with an activation energy of 0.845eV, which is expected to be applied to medium and low temperature solid oxide fuel cell electrolyte materials.

Description

technical field [0001] The invention relates to the technical field of solid electrolyte preparation, in particular to a Ca-W mixed-doped Bi 2 o 3 Preparation method of solid electrolyte. Background technique [0002] Solid oxide fuel cell (SOFC) has become a research hotspot in the field of new energy due to its unique all-solid structure, high energy conversion efficiency, environmental friendliness, reliability, wide range of fuel use, low loss, and long life. Traditional SOFC has a high operating temperature (800-1000°C) and has high requirements on the performance of related materials, which limits the development and application of SOFC. Therefore, the development of medium and low temperature SOFC has become an inevitable trend. Solid electrolyte materials are the key components of SOFCs, so the development of high-conductivity electrolyte materials is crucial to the development and application of SOFCs. Bi 2 o 3 The base electrolyte material has high oxygen ion ...

AI Technical Summary

Problems solved by technology

Bi 2 o 3 base electrolyte, although it is possible to achieve high conductivity, compared to stable cubic ZrO at the same temperature 2 Two orders of magnitude higher, but Bi 2 o 3 And the material will undergo a phase change during the heating and cooling process, and at the same time, it is easy to be reduced to metal Bi under low oxygen partial pressure, which limits its application in SOFC.

To suppress the phase transition, improve the Bi 2 o 3 The conductivity of the base electrolyte material, although some scientific and technological workers use ion doping can effectively suppress the phase transition, thereby keeping the high-temperature phase with higher conductivity to a lower temperature, but in the case of low oxygen partial pressure or reducing atmosphere The problem that it is extremely easy to be reduced to metals and lead to electronic conduction has always been a headache in this field.

The research on bismuth tungstate in fuel cell electrolyte is not deep enough, the main reason is that WO 3 Doped Bi 2 o 3 Ionic conductivity is lower than that of Y 2 o 3 Doped Bi 2 o 3 electrolyte

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