ABSTRACT

To study the structural, electronic, elastic, thermodynamical and thermoelectric (TE) properties of copper nitride ($C{u}_{n}N$ with n=1, 3, 4), we have used density functional theory (DFT) based on the generalized gradient approximation and semi-classical Boltzmann transport theory. The band structure and electronic density of states (DOS) confirm that $C{u}_{3}N$ has a semiconductor behavior with an indirect bandgap of 0.32 eV, however, CuN and $C{u}_{4}N$ have metallic behavior. The study of elastic constants and their derived parameters of $C{u}_{n}N$ in cubic structure revealed that the compounds are ductile, mechanically and dynamically stable and have an ionic bond. This study shows that the hardness and thermal stability of $C{u}_{n}N$ increase with n increase from 1 to 4. The TE properties are calculated and found to decrease with n. The calculated values of ZT are 0.975, 0.84 and 0.023 at 300 K, which makes CuN and $C{u}_{3}N$ are good candidates for thermoelectric applications.

摘要

研究氮化铜的结构、电子、弹性、热力学和热电 (TE) 特性（$C{你}_nñ$在n = 1, 3, 4) 的情况下，我们使用了基于广义梯度近似和半经典玻尔兹曼输运理论的密度泛函理论 (DFT)。能带结构和电子态密度 (DOS) 证实了$C{你}_3ñ$具有间接带隙为 0.32 eV 的半导体行为，然而，CuN和$C{你}_4ñ$有金属行为。弹性常数及其派生参数的研究$C{你}_nñ$在立方结构中表明，这些化合物具有延展性、机械和动态稳定性，并具有离子键。本研究表明，硬度和热稳定性$C{你}_nñ$随着 n 从 1 增加到 4 增加。计算 TE 特性并发现它随着 n 减小。ZT 的计算值在 300 K 时分别为 0.975、0.84 和 0.023，这使得CuN和$C{你}_3ñ$是热电应用的良好候选者。