Open-circuit voltage of ceria-based thin film SOFC supported on nano-porous alumina

Thin film electrolytes/electrodes supported on porous substrates are needed for micro-SOFC (Solid Oxide Fuel Cell). In this study, we have tested the possible use of GDC (Gd2O3-doped CeO2) thin film as an electrolyte by measuring the open-circuit voltage (OCV) and power density of the cell. Anodic nano-porous alumina membrane was used as a porous, supporting substrate onto which the porous Pt thin film as an anode was deposited. GDC thin film (∼ 2 μm) was deposited on the top of the Pt anode by pulsed laser deposition (PLD). In order to measure the conductivity of GDC film and the power density of the cell, another Pt electrode as a cathode was painted on the surface of the GDC thin film. The measured OCV was lower than the theoretical OCV below 600 °C, however, close to the bulk GDC value. Thus, much of the reduced OCV at or below 500 °C was possibly attributed to the low catalytic activity of Pt electrodes. Enhanced OCV and power density are expected for the electrodes using highly active materials.