Enhanced performance of intermediate temperature-solid oxide fuel cells with a bimodal shape Nd0.2Ce0.8O2-delta electrolyte

Abstract

To reduce the operating temperature of solid oxide fuel cells (SOFCs), we develop a highly conductive, bimodal-shape Nd0.2Ce0.8O2-delta (NDC) materials at an intermediate temperature (IT) with excellent sinterability for the anode-supported cell design. The advanced bimodal NDC composite materials consist of powders synthesized by both the glycine-nitrate process and coprecipitation methods. The bimodal NDC electrolyte shows 2-3 fold higher conductivity than that of singly processed NDC electrolytes in the IT range. Further, this doubly processed highly conductive NDC material for the electrolyte and composite cathode significantly improves the performance of the anode-supported configuration of IT-SOFCs. This is due to the rapid transport of oxygen-ions in the electrolyte, small grain sizes of the bimodal cathode with a high porosity, and the improved interfacial property between the electrolyte and cathode, which results in decreased ohmic and polarization resistance of bimodal-based cells at 550 -650 degrees C. (C) 2017 Elsevier B.V. All rights reserved.