Nanocrystalline Gadolinium doped Ceria (Ce0.8Gd0.2O3-δ) for oxygen sensor and solid oxide fuel cell applications

Gadolinium doped Ceria (GDC) is a known oxygen ion conductor in intermediate temperature range. This is a preliminary work aimed at exploring the suitability of using nanocrystalline GDC as oxygen sensor in intermediate operating temperature range (500°C–700°C). The nanocrystalline Gadolinium doped Ceria (GDC) has been prepared by sol-gel method with EDTA as chelating agent. Particle size around 10±5nm was obtained after calcination at 600°C. Pellets prepared using this material were sintered 1350°C, which show 90% of the theoretical density. The dc and ac (1Hz–1MHz) conductivity of these pellet was measured in the temperature range 200–600°C and 500–700°C respectively. Highest conductivity of the order of 4.61X10⁻⁵ S/cm was recorded at 700°C. Possible reasons for low conductivity are discussed.