利用脉冲激光沉积技术制备了SrTi0.8Nb0.2O3/Au纳米复合热电薄膜并研究了Au纳米颗粒的含量对薄膜热电性能的影响.实验结果表明,随着薄膜中Au纳米颗粒含量的增加,复合薄膜的载流子浓度和迁移率同时减小,导致复合薄膜的电阻率增大;此外,随着Au纳米颗粒含量的增加,复合薄膜的塞贝克系数绝对值因载流子浓度的增大及Au和SrTi0.8Nb0.2O3界面势垒的能量过滤效应而增大.当Au原子百分比为0.94%时,复合薄膜的功率因子达到最大值,表明少量的纳米Au颗粒掺入可以有效地提升SrTi0.8Nb0.2O3薄膜的热电性能.
In this work, SrTi0.8Nb0.2O3/Au nanocomposite thin films were fabricated by pulsed laser deposition(PLD)method, and the effect of Au nanoparticles content on the thermoelectric properties of the films were investigated.With the increase of Au nanoparticles content, the electrical resistivity of the films increases due to the decreased carrier concentration and mobility.The absolute value of Seebeck coefficient of the films is also found to increase with the Au nanoparticles content, which is mainly caused by the increased carrier concentration and the carrier energy filtering effect of the interface barrier between Au and SrTi0.8Nb0.2O3.The film sample with Au nanoparticles content of 0.94% has the best power factor, indicating that the incorporation of a small amount of Au nanoparticles can improve the thermoelectric performance of SrTi0.8Nb0.2O3 thin films.
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