关键词: Al掺杂ZnO多晶;一次烧结;二次烧结;热电输运;饱和固溶度

Abstract: Zn1-xAlxO(0≤x≤0.005) polycrystalline bulks with hexagonal wurtzite structure were prepared by solid-state reaction method.The micro morphology and the thermoelectric properties of Zn1-xAlxO bulk were investigated.Doping Al made ZnO grain increased and grain boundary decreased.The results show that the spinel ZnAl2O4 appeared while x=0.005.Secondarily sinterd samples have 1-2 orders of magnitude decrease of resistivity.The semiconductor behavior of bulks transform metallic behavior after Al doping in ZnO.Al doping is responsible for the carrier concentration and mobility remarkable increase.At x=0.004 the minimum of resistivity of primarily sintered sample is 10 mΩ·cm.The seebeck coefficient and power factor S2/ρ increase with the increasing temperature at 300-950 K.The maximum of the power factor is 0.11 mW/m·K2 at room temperature.The saturated solution of Al doping in ZnO is between 0.004 and 0.005.

Key words: Zn1-xAlxO polycrystalline bulks;primarily sintered;secondarily sintered;thermoelectric property;saturated solution