Effect of Ho Doping on the High-Temperature Thermoelectric Properties of Ca3Co4O9-Based Oxides
Ca3-xHoxCo4O9 (x=0.0, 0.15, 0.3, 0.45) samples were prepared using solid reaction and the effect of Ho doping on their high thermoelectric properties were investigated. The substitution of Ho for Ca resulted in an increase of both thermopower and electrical resistivity which could be attributed to the decrease of hole concentrations. The Ho-doped samples had lower thermal conductivity than Ca3Co4O9 due to their lower electronic and lattice thermal conductivity. The largest ZT values were attained in Ca2.7Ho0.3Co4O9 sample.
T. Zhu and J. M. Zhou, "Effect of Ho Doping on the High-Temperature Thermoelectric Properties of Ca3Co4O9-Based Oxides", Advanced Materials Research, Vols. 228-229, pp. 947-950, 2011