(Bi2O3)1-x-y(Dy2O3)x(Ho2O3)y üçlü sistemin elektriksel, yapı ve termal kararlılık özelliklerinin incelenmesi

Bu çalışmanın amacı; zamanla özellikleri bozulmayan ve çalışma şartları altında iyonik iletkenliğini koruyan elektrolit/elektrolitler tespit etmektir. Bu doğrultuda, (Bi2O3)1-xy(Ho2O3)x(Dy2O3)y üçlü sistemin (x=%11, 12, 13, 14 mol ve y=% 4, 3, 2, 1 mol, katkı konsantrasyonu) numuneleri katıhal reaksiyonu ile 48 saat 750°C ısıl işleme tabi tutularak hazırlandı. Katı Oksit Yakıt Hücresi (SOFC) için en iyi katı elektrolit özelliklere sahip olabilecek numunelerin yapısal özellikleri X-ışınları difraktometresi (XRD), elektriksel özellikleri dört-nokta metodu ve termal özellikleri diferansiyel termal analiz (TG / DTA) ölçüm sistemleri ile ölçüldü. XRD ölçümleri 48 saat 750°C ısıl işlem sonucunda bütün numuneler δ- Bi2O3 fazında kararlı olduğunu gösterdi.

Anahtar Kelimeler:

Katıhal reaksiyonu, Yakıt hücresi, Elektriksel iletkenlik, Dört-nokta metod

Investigation of electrical, structural and thermal stability properties of (Bi2O3)1-x-y(Dy2O3)x(Ho2O3)y ternary system

The aim of this study is to find an electrolyte which does not have any degradation in its properties with time this maybe caused either interaction between the different electrochemical cell materials or by instability of the ionic conductor under operation conditions. Accordingly, this (Bi2O3)1-x-y(Ho2O3)x(Dy2O3)y ternary system (x=11, 12, 13, 14 mol % and y=4, 3, 2, 1 mol %, dopant concentrations) sample materials were synthesized using solid state reaction method sintering each of them at 750°C for 48 hours. Structural, electrical and thermal properties of the samples which are candidate of electrolyte for solid oxide fuel cells have been evaluated by means of X-ray diffraction (XRD), four-probe method, and thermal analysis (TG / DTA). XRD measurements showed that all of the samples have stable δ- type phase which was also supported by the TG / DTA measurements.

Keywords:

Electrolyte Solid state reaction, Fuel cell, Electrical conductivity, Fourprobe point method,

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