The system Ce0.8La0.2−xTlxO2−δ (TxLDC) has been investigated for the first time.
The conductivity of T0.07LDC is 3 × 10−2 Scm−1 at 650 °C with low activation energy.
Its conductivity is higher than the maximum value reported for the SDC and GDC.
T0.07LDC is much less costly than that of SDC and GDC.