设为首页 加入收藏 登录旧版
氮掺杂ZrC和TaC结构和电子性质的第一性原理研究
  
DOI:
中文关键词:  
英文关键词:
基金项目:
作者单位
刘尚,刘士余,张硕鑫,严达利,余浅,任海涛,于彬,李德军  
摘要点击次数: 99
全文下载次数: 66
中文摘要:
      为了研究氮(N)掺杂对难熔金属碳化物ZrC和TaC的影响,本文运用第一性原理超原胞方法(SC)和虚晶近似方法(VCA)进行了研究。计算了掺杂不同浓度N原子的ZrC1-xNx和TaC1-xNx,(0≤X≤1)难熔金属碳氮化物的形成能、晶格常数、体积以及电子态密度。形成能计算结果表明ZrC1-xNx和TaC1-xNx的稳定性随氮浓度的增大而增强;晶格常数和体积随氮浓度的增大而减小,结构也越来越稳定;氮掺杂导致的电子态密度在深能级处的新峰随着氮浓度的增大而变高,也表明结构更稳定。此外,比较相同N浓度下的ZrC1-xNx和TaC1-xNx,发现ZrC1-xNx的形成能更低,因此掺杂相同浓度的N时ZrC1-xNx更稳定。
英文摘要:
      To investigate the influence of impurity of nitrogen (N) in the cubic ZrC and TaC,first-principle calculations with supercell (SC)method and virtual crystal approximation (VCA)method were performed in the present study.The formation energy,lattice constant,volume and electronic density of states of ZrC1-xNxand TaC1-xNx,(0≤X ≤1) compounds doped with different concentrations of nitrogen atoms were calculated respectively. The formation energy shows that the stability of ZrC1-xNx and TaC1-xNx increases with the increase of nitrogen concentration. The lattice constant and volume decrease with the increase of nitrogen concentration, which indicate the structure becomes more and more stable. The new peak of density of state(DOS) at the deep energy level becomes higher with the increase of nitrogen, which also suggests that the structure is more stable with the increase of nitrogen. In addition, comparing the stability of ZrC1-xNx and TaC1-xNx at the same N concentration,it was found that the impurity formation energy of ZrC1-xNx was lowerthan that of TaC1-xNx so the ZrC1-xNx was more stable.
查看全文  查看/发表评论  下载PDF阅读器