Enhanced Thermoelectric Performance of ZnO-Based Thin Films via Interface Engineering

Zinc oxide (ZnO) is a potential thermoelectric material with good chemical and thermal stability as well an excellent Seebeck coefficient. However, the extremely low carrier concentration brings poor electrical transport properties. Although Gallium (Ga) doping could increase of ZnO film, its performance still limited due to deteriorated coefficient enhanced conductivity. Interface engineering effective strategy decouple electron-phonon interaction for materials. Thus, in this work, GZO (Ga-doped ZnO)/NAZO (Ni, Al co-doped ZnO) multilayer films were designed further improve properties films. It was found that GZO/NAZO possessed better conductivity, which attributed increased Hall mobility. Meanwhile, benefiting from energy filtering occurred at interfaces, density states mass increased, resulting comparable values. Ultimately, power factor value 313 ?W m?1 K?2 achieved almost 46% larger than film. This work provides paradigm optimize other systems by structure design coherent interfaces.