Azam Sikander, Umer Muhammad, Saeed Umer, Khan Wilayat, Irfan Muhammad, Abbas Zeesham, Kityk I V
Faculty of Engineering and Applied Sciences, Department of Physics, RIPHAH International University I-14 Campus Islamabad, Pakistan.
Department of Physics, The University of Lahore, Sargodha Campus, 40100, Sargodha, Pakistan.
J Mol Graph Model. 2020 Jan;94:107484. doi: 10.1016/j.jmgm.2019.107484. Epub 2019 Oct 31.
We explore influence of Mg alloying effect on electronic band structure dispersion and thermoelectric properties of tin chalcogenide materials. Based on density functional theory (DFT) within a framework of full potential linearized augmented plane wave method (FP-LAPW), we evaluate the energy band structure and optical properties of MgSnSe (x = 6%, 12% and 18%) materials. Moreover, we extend our calculations to simulate the electrical transport properties using Boltzmann transport theory. Within the approximations employed in our calculations the theoretically predicted band energy gap values and the temperature dependence of electrical transport properties of MgSnSe compounds revealed that the Mg-alloying have enhanced thermoelectric features. To verify the quality of calculations the comparison with the experimental absorption spectra are presented. The better thermoelectric performance in MgSnSe is expected to occur for all doping concentrations, however 18% Mg-doped material exhibits higher value of Seebeck coefficient and lower thermal conductivity which is suggestive that at higher Mg concentration the holes become dominant over electrons and hence make these materials to be more promising candidates for their use in thermoelectric power generation and in cooling devices.
我们探讨了镁合金化效应对锡硫属化物材料电子能带结构色散和热电性能的影响。基于全势线性缀加平面波方法（FP-LAPW）框架内的密度泛函理论（DFT），我们评估了MgSnSe（x = 6%、12%和18%）材料的能带结构和光学性质。此外，我们利用玻尔兹曼输运理论扩展计算以模拟电输运性质。在我们计算所采用的近似范围内，理论预测的MgSnSe化合物的带隙能量值和电输运性质的温度依赖性表明，镁合金化增强了热电特性。为了验证计算的质量，我们给出了与实验吸收光谱的比较。预计在所有掺杂浓度下MgSnSe都具有较好的热电性能，然而18% Mg掺杂的材料表现出更高的塞贝克系数值和更低的热导率，这表明在较高的镁浓度下，空穴比电子占主导地位，因此使这些材料更有希望用于热电发电和冷却装置。
