51. Effect of various doping on electrochemical properties of KNbO3 proton conductor.
- Author
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Li, Hongzheng, Li, Ying, Huang, Wenlong, and Ding, Yushi
- Subjects
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SOLID state proton conductors , *CONDUCTIVITY of electrolytes , *SOLID electrolytes , *CHEMICAL stability , *DOPING agents (Chemistry) , *SOLID-phase synthesis - Abstract
KNbO 3 and KNb 0.9 M 0.1 O 3-α (M = Ti, Hf, Zr, Sc, In, Yb) were prepared by solid state reaction at 920 °C for 4 h and characterized by X-ray diffraction. The electrical properties of solid electrolytes were measured by AC impedance in wet air, wet Ar and dry Ar. The order of conductivity in different atmospheres is σ (wet air)> σ (wet Ar)> σ (dry Ar). Among KNb 0.9 M 0.1 O 3-α (M = Ti, Hf, Zr, Sc, In, Yb), KNb 0.9 In 0.1 O 3-α displays the highest conductivity. The carriers transport numbers of each material were measured by concentration cell method. The results show KNb 0.9 In 0.1 O 3-α is almost a pure proton conductor below 625 °C. KNb 0.9 In 0.1 O 3-α has excellent chemical stability against CO 2 and H 2 O, but in the process of use should avoid rapid heating and cooling. • KNbO 3 , a new type of proton conductor, was prepared by solid-phase synthesis method. High density solid electrolytes were obtained by sintering at 950°C for 4h. Compared with traditional proton conductor, the sintering temperature is greatly reduced and the sintering time is shortened. • The effects of different doping elements on the electrical properties of KNbO 3 proton conductors were studied for the first time. In this study, we consider that the radius and valence of the doped elements together affect the conductivity of the solid electrolytes. • The tolerance of the material to CO 2 and H 2 O and the thermal cycle stability were tested. The material has excellent chemical stability against CO 2 and H 2 O, but rapid heating and cooling should be avoided in the process of use. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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