Lattice thermal conductivities of zirconium carbide (ZrC_x, x = 1, 0.75 and 0.5) ceramics with different carbon vacancy concentrations were calculated using a combination of first-principles calculations and the Debye-Callaway model. The Grüneisen parameters, Debye temperatures, and phonon group velocities were deduced from phonon dispersions of ZrC_x determined using first-principles calculations. In addition, the effects of average atomic mass, grain size, average atomic volume and Zr isotopes on the lattice thermal conductivities of ZrC_x were analyzed using phonon scattering models. The lattice thermal conductivity decreased as temperature increased for ZrC, ZrC_0.75 and ZrC_0.5 (Zr₂C), and decreased as carbon vacancy concentration increased. Intriguingly, ZrC_x can be tailored from a thermal conducting material for ZrC with high lattice thermal conductivity to a thermal insulating material for ZrC_0.5 with low lattice thermal conductivity. Thus, it opens a window to tune the thermal properties of ZrC_x by controlling the carbon vacancy content.

 使用第一性原理计算和Debye-Callaway模型的组合，计算了具有不同碳空位浓度的碳化锆陶瓷（ZrC _x，x = 1、0.75和0.5）的晶格热导率。Grüneisen参数，德拜温度和声子基团速度是通过使用第一性原理计算确定的ZrC _x声子色散推导出来的。此外，使用声子散射模型分析了平均原子质量，晶粒尺寸，平均原子体积和Zr同位素对ZrC _x晶格热导率的影响。ZrC，ZrC _0.75和ZrC _0.5（Zr₂ C），并且随着碳空位浓度的增加而降低。有趣的是，ZrC _x可以从具有高晶格导热率的ZrC导热材料调整为具有低晶格导热率的ZrC _0.5隔热材料。因此，它通过控制碳空位含量打开了一个窗口，以调节ZrC _x的热性能。