Nanostructured p-type Cr/V2O5 thin films with boosted thermoelectric properties

The urgent need for non-toxic and abundant thermoelectric materials has become a significant motivation to improve the figures of merit of metal oxides in order to remove the barrier towards their widespread use for thermoelectric applications. Here we show the influence of a Cr layer in boosting the thermoelectric properties of vanadium pentoxide (V2O5) thin films, deposited by thermal evaporation and annealed at 500 degrees C. The Cr to V2O5 thickness ratio controls the morphological and thermoelectric properties of the thin films produced. The optimized Seebeck coefficient and power factor values at room temperature are +50 mu V K-1 and 7.9 x 10(-4) W m(-1) K-2, respectively. The nanograin structure of the films is responsible for an improvement in the electrical conductivity up to 3 x 10(5) (Omega m)(-1) with a typical thermal conductivity of 1.5 W m(-1) K-1. These results combine to yield promising p-type thermoeletric CrV2O5 thin films with a ZT of 0.16 at room temperature.