Enhanced thermoelectric power factor of Bi2Sr2Co2Oy thin films by incorporating Au nanoparticles

c-Axis oriented Bi2Sr2Co2Oy thin films imbedded with Au nanoparticles were prepared by pulsed laser ablation a ceramic Bi2Sr2Co2Oy target with a small piece of Au foil overlapped. It was found that the incorporation of Au nanoparticles, about 5-15 nm in diameter, did not disrupt the c-axis orientation of the films. Fortunately, the incorporation of Au nanoparticles decreased the resistivity of Bi2Sr2Co2Oy films while maintained the Seebeck coefficient almost unchanged, thus resulted in an enhanced power factor. Possible mechanisms were proposed to explain the results. This work demonstrated a promising approach to optimize the thermoelectric performance of layered cobaltite thin films. (C) 2015 Elsevier Ltd. All rights reserved.