High‐Temperature Transport Property of In2−xCexO3
(0 ≤ x ≤ 0.10) Fine Grained Ceramics
Using the spark plasma sintering process In2−x
O3 (0 ≤ x ≤ 0.10) fine
grained ceramics have been synthesized. Our results indicate that all the In2O3‐based ceramic samples show good electrical conductivity and high thermoelectric power factor. In
comparison with pure In2O3 bulks or doped samples with grain size above 1 μm, the 100–300 nm fine grain In2O3‐based
ceramics exhibit much lower thermal conductivities (1.9–2.5 W·(m·K)−1 at 1173 K), demonstrating a remarkable cooperative tuning effect imposed by grain size reduction and nano‐clusters formation. The maximum figure of merit ZT
value is optimized up to ~0.47 at 1223 K for In1.92Ce0.08O3 sample, which makes them promising candidates for thermoelectric applications.