A novel series of samples Sn1−xGaxP2O7 (x = 0.00, 0.01, 0.03, 0.06, 0.09, 0.12, 0.15) was synthesized by solid state reaction. XRD patterns indicated that the samples of x = 0.00 − 0.09 exhibited a single cubic phase structure, and the doping limit of Ga3+ in Sn1−xGaxP2O7 was x = 0.09. The protonic and oxide-ionic conduction in Sn1−xGaxP2O7 were investigated using some electrochemical methods at intermediate temperatures (323–523 K). It was found that the samples exhibited appreciable protonic conduction in hydrogen atmosphere, and a mixed conduction of oxide-ion and electron hole in dry oxygen-containing atmosphere. The highest conductivities were observed for the sample of x = 0.09 to be 4.6 x 10−2S/cm in wet H2 and 2.9 x 10−2 S cm−1 in dry air at 448 K, respectively. The H2/air fuel cell using x = 0.09 as electrolyte (thickness: 1.45mm) generates a maximum power density of 19.2 mW/cm2 at 423K and 22.1mW/cm2 at 448K, respectively.

Intermediate Temperature Ionic Conduction in Sn1−xGaxP2O7. H.Wang, J.Liu, W.Wang, G.Ma: Journal of Power Sources, 2010, 195[17], 5596-600