Ca掺杂对ZnO氧化物热学性能的影响

在密度泛函理论和线性响应的密度泛函微扰理论基础上的第一性原理计算的方法研究了Ca掺杂对纤锌矿结构氧化物ZnO热学参数和热学性能的影响。研究结果表明，Ca掺杂ZnO氧化物晶格a，b，c轴均有所增大；在计算温度区间，纯的ZnO和Ca掺杂的ZnO的晶格热容均随温度升高不断增大；Ca掺杂的ZnO具有较高的晶格热容；纯的ZnO和Ca掺杂的ZnO的晶格热容在最高温度900K分别达到16.5 Cal.mol-1K-1和31.7Cal.mol-1K-1。纯的ZnO和Ca掺杂的ZnO的德拜温度 均随温度升高不断增大，Ca掺杂的ZnO的德拜温度 均高于纯的ZnO。Ca掺杂在ZnO中引入了新的振动模式。Ca掺杂ZnO氧化物应该具有较高的晶格热导率。

Effects of Ca Doping on Thermal Properties of ZnO Oxide

The thermal consants and the thermal transport properties of the Ca doped wurrite type ZnO have been investigated by ab-initial calculations based on the density functional theory as well as the linear response density perturbation functional theory. The results show that the Ca doped wurrite type ZnO has increased lattice constants a, b and c. The lattice heat capacity increases with increasing temperature for both systems, the Ca doped system has higher lattice heat capacity, and the heat capacities reach 16.5 Cal.mol-1K-1 and 31.7Cal.mol-1K-1 for the pure ZnO and the Ca doped ZnO at 900K, respectively. The Debye temperature increases with increasing temperature for both systems, and the Ca doped system has higher Debye temperature value than that of the pure ZnO system. New vibrational modes has been introduced by Ca doping, and the Ca doped ZnO system should have higher lattice thermal conductivity.