Electrical Conductivity of Y3+-doped Ba(Ce,Zr)O3 in Wet Nitrogen Atmosphere

• Published in: Journal of Physics: Conference Series
• Main Author: Affandi N.S.M.; Osman N.; Hassan O.H.
• Format: Conference paper
• Language: English
• Published: Institute of Physics Publishing 2018
• Online Access: https://www.scopus.com/inward/record.uri?eid=2-s2.0-85054364042&doi=10.1088%2f1742-6596%2f1083%2f1%2f012027&partnerID=40&md5=27b7f54ad52ad336185b8290ef5134b4

Proton conducting ceramics such as barium cerate-zirconate oxide, Ba(Ce,Zr)O3 is one of promising candidates to be used as an electrolyte material in intermediate temperature solid oxide fuel cell (IT-SOFC). In this work, single-phase of BaCe0.54Zr0.36Y0.1O2.95 (BCZY) powder was successfully prepared using a sol-gel method. The powder was pressed into a pellet with diameter, d = 13 mm and thickness, t = ∼1-2 mm using an uniaxial pressing technique with pressure of 369 MPa for 5 minutes. The pellet with relative density of 92% was obtained after underwent two-step sintering (TSS) method at T1 = 1500°C and T2 = 1450°C with holding time 1 minute and 12 hours respectively. Impedance data of the sample with grain in sub-micron size (as measured by SEM) was collected using an impedance spectroscopy (IS) in wet nitrogen atmosphere at temperature ranging from 500 to 800°C. All responses in the impedance spectrum were separated and fitted accordingly to an equivalent circuit based on a brick-layer model (BLM) with equivalent circuit of R1|Q1-R2|Q2. Analysis of the impedance spectrum showed the sub-micron grain resulted in high grain boundary resistance with conductivity of 10-4 S cm-1 at 500 °C to 700 °C. The conductivity of the sample was thermally activated and obeyed Arrhenius behavior with activation energy (Ea) of 0.76 eV. © Published under licence by IOP Publishing Ltd.