Microstructure and electrical conductivity of core‐shell structured YDC@xBCY (x = 0.6, 0.8, 1, 1.2, and 1.4) ceramics

Abstract The core‐shell structured nanopowders of Ce 0.9 Y 0.1 O 2‐δ @xBaCe 0.9 Y 0.1 O 3‐δ (YDC@xBCY, x = 0.6, 0.8, 1, 1.2, and 1.4) were synthesized via a co‐precipitation method and then sintered in air atmosphere at 1600 ° C to obtain dense ceramic pellets. XRD, SEM, and EDS analyses confirm that the YDC@BCY core‐shell structure remains in bulk ceramics after sintering. Among all samples, YDC@1BCY exhibits the highest total conductivity in air (1.40 × 10 −4 to 1.05 × 10 −2 S/cm in 350°C–550°C). In a 10% H 2 ‐90% N 2 atmosphere, the proton conductivity of YDC@xBCY peaks at x = 0.8. With the aid of the core‐shell structure design, YDC/BCY heterogeneous interface networks are constructed, and the interconnected high conductive YDC/BCY heterogeneous interface networks facilitate ionic transport within the sample. The core‐shell design offers a promising strategy for improving the ionic conductivity of doped CeO 2 –BaCeO 3 ‐based composite ceramics.