论文部分内容阅读
为研究掺杂对材料热电性能的影响,用新溶胶凝胶法合成SrO(Sr_(1-x)La_xTiO_3)_n(n=1,2,∞)陶瓷材料,测试其热电性能,其中包括电导率和Seebeck系数(S)。层状结构的SrO(Sr_(1-x)La_xTiO_3)_n(n=1,2)电导率明显低于非层状结构,这是由于有绝缘的SrO层而造成。n=1和n=∞的2个试样在室温时的Seebeck系数相近,均为-99.39μV K~(-1)。为研究材料性能与结构的关系,使用密度泛函理论计算SrO(SrTiO_3)_n和SrO(Sr_(1-x)La_xTiO_3)_n(n=1,2,∞)材料的带状结构(band structure)、总态密度(total density of states)和局部态密度(partial density of states)。其电子结构明显呈二维特性。SrO(Sr_(1-x)La_xTiO_3)_n(n=1,∞)中Ti3d轨道费米能级附近态密度近似相等,等于1.05eV。这代表SrO(Sr_(1-x)La_xTiO_3)_n(n=1,∞)在低温具有相近的Seebeck系数。计算与实验结果相符。
In order to study the effect of doping on the thermoelectric properties of the material, SrO (Sr_ (1-x) La_xTiO_3) _n (n = 1,2, ∞) ceramic materials were synthesized by a new sol-gel method and tested for their thermoelectric properties including conductivity And Seebeck coefficient (S). The SrO (Sr_ (1-x) La_xTiO_3) _n (n = 1,2) conductivity of the layered structure is significantly lower than that of the non-layered structure due to the insulating SrO layer. The Seebeck coefficients of the two samples with n = 1 and n = ∞ at room temperature were similar, all of which were -99.39μV K -1. In order to study the relationship between material properties and structure, the band structure of SrO (SrTiO_3) _n and SrO (Sr_ (1-x) La_xTiO_3) _n (n = 1,2, Total density of states, and partial density of states. Its electronic structure obviously showed two-dimensional characteristics. The density of states of the Ti3d orbit Fermi near the Fermi level in SrO (Sr_ (1-x) La_xTiO_3) _n (n = 1, ∞) is approximately equal to 1.05eV. This means that SrO (Sr_ (1-x) La_xTiO_3) _n (n = 1, ∞) has similar Seebeck coefficients at low temperature. Calculation and experimental results.