• Basu, Suddhasatwa
• Lund, Peter D.
• Asghar, Imran
• Khan, Ieeba

Abstract

<p>Composite electrolytes of lithium, sodium, and potassium carbonate ((LiNaK)₂CO₃),and samarium doped ceria (SDC) have been synthesized and the carbonatecontent optimized to study conductivity and its performance inintermediate-temperature solid oxide fuel cell (IT-SOFC). Electrolytecompositions of 20, 25, 30, 35, 45 wt% (LiNaK)₂CO₃–SDCare fabricated and the physical and electrochemical characterization iscarried out using X-ray diffraction, scanning electron microscopy,electrochemical impedance spectroscope, and current–voltagemeasurements. The ionic conductivity of (LiNaK)₂CO₃–SDC electrolytes increases with increasing carbonate content. The best ionic conductivity is obtained for 45 wt% (LiNaK)₂CO₃–SDC composite electrolyte (0.72 S cm⁻¹ at 600 °C) followed by the 35 wt% (LiNaK)₂CO₃–SDC composite electrolyte (0.55 S cm⁻¹ at 600 °C). The symmetrical cell of the 35 wt% (LiNaK)₂CO₃–SDCcomposite electrolyte with lanthanum strontium cobalt ferrite (LSCF)electrode in air gives an area specific resistance of 0.155 Ω cm² at 500 °C. The maximum power density of the fuel cell using 35 wt% (LiNaK)₂CO₃–SDC composite electrolyte, composite NiO anode and composite LSCF cathode is found to be 801 mW cm⁻² at 550 °C.</p>

Topics

• density
• impedance spectroscopy
• scanning electron microscopy
• x-ray diffraction
• Sodium
• Strontium
• composite
• Potassium
• Lanthanum
• cobalt
• Lithium
• Samarium