  The correlated couple of electrical and thermal property is the challenge to
realize a substantial leap in thermoelectric materials.Synthesis of
semiconductor and metal composites is a significant and versatile design
strategy to optimize the thermoelectric performance driven by tailored
interface between nanoinclusions and matrix.In this study, we present the
simultaneous increase of electrical conductivity and Seebeck coefficient, and
reduction of thermal conductivity in Sb2Te3-Au system.The enhanced electrical
conductivity lies in the incorporated Au nanostructures contributing to
injecting carriers to Sb2Te3 matrix.The appropriate barriers originated from
the Au-Sb2Te3 interface, which filter low energy carriers, results in
enhancement of Seebeck coefficient.The increased boundaries and nanodomains
block the transport of phonons, subsequently reducing the thermal
conductivity.As a consequence, combination of these effects promote double of
ZT value in 1% Au@ Sb2Te3 composites with respect to the pristine Sb2Te3.
