3D Superlattice Ceramics of SrTiO3

In recent years, the quantum confinement, energy filtering and interfacial phonon scattering effects were usually used to improve the thermoelectric (TE) per- formance of composite materials. In this chapter, by taking SrTiO3 (STO) ceramic as an example, these three effects were quantitatively investigated. First an STO- based 3D superlattice ceramic with 2D electron gas grain boundaries (GBs) were designed to utilize the three effects. Then the transport coefficients and ZT value as functions of carrier concentration, grain size, GB thickness, GB potential barrier heightandtemperaturewerecalculatedbyusingBoltzmanntransportequations.The optimum parameters of STO ceramics for ZT > 1@300K were also determined. These results will aid in the design of environmental friendly nanostructured oxide ceramics with high TE performance.