材料期刊网

Thermoelectric and thermodynamic properties of a series of Ca-site rare-earth R(3+) doped Ca(3)Co(4)O(9) were investigated. For a fixed doping level, with the reduction in R(3+) radius, thermopower is found to gradually increase despite the carrier concentration remains unchanged. The scaling behavior between thermopower and electron specific heat coefficient reveals that the additional increase in thermopower originates from enhanced electron correlation which may be attributed to doping-induced chemical pressure. (C) 2010 American Institute of Physics. [doi:10.1063/1.3479923]