研制开发新型的光电材料对促进社会经济发展具有重要的科学意义和实用价值.利用宽禁带CuInO_2铟基材料实现全透明光电材料是目前深入研究的热点.通过基于密度泛函的第一性原理计算方法,本文计算出掺杂元素Mg, Be, Mn在CuInO_2的形成能....研制开发新型的光电材料对促进社会经济发展具有重要的科学意义和实用价值.利用宽禁带CuInO_2铟基材料实现全透明光电材料是目前深入研究的热点.通过基于密度泛函的第一性原理计算方法,本文计算出掺杂元素Mg, Be, Mn在CuInO_2的形成能.计算结果表明,施主类缺陷(如掺杂元素替代Cu原子或进入间隙位置)由于较高的形成能和较深的跃迁能级,很难在CuInO_2材料中出现N型导电;而受主缺陷中,在氧原子化学势极大的情况下, Mg原子替代In能成为CuInO_2理想的受主缺陷.计算结果可为制备性能优异的CuInO_2材料提供指导.展开更多
为研究碳表面对甲烷的吸附特性,采用基于密度泛函理论的第一性原理方法系统地研究了甲烷分子吸附在碳表面后的电子态密度、功函数和吸附能,同时研究了碳的表面能、层间弛豫与表面厚度之间的关系。计算结果表明,层间弛豫是由于相邻层间...为研究碳表面对甲烷的吸附特性,采用基于密度泛函理论的第一性原理方法系统地研究了甲烷分子吸附在碳表面后的电子态密度、功函数和吸附能,同时研究了碳的表面能、层间弛豫与表面厚度之间的关系。计算结果表明,层间弛豫是由于相邻层间的弱相互作用引起的;顶位是甲烷最稳定的吸附部位;甲烷的吸附位置位于碳的碳原子上方3.21处,吸附能为-0.133 e V,与碳表面厚度关系不大;因少量电荷从碳表面转移到甲烷分子,甲烷吸附会使功函数略有增强。展开更多
Using the first-principles methods, we study the formation energetics properties of intrinsic defects, and the charge doping properties of extrinsic defects in transparent conducting oxides CuCrO2. Intrinsic defects, ...Using the first-principles methods, we study the formation energetics properties of intrinsic defects, and the charge doping properties of extrinsic defects in transparent conducting oxides CuCrO2. Intrinsic defects, some typical acceptortype, and donor-type extrinsic defects in their relevant charge state are considered. By systematically calculating the formation energies and transition energy, the results of calculation show that, Vcu, Oi, and Ocu are the relevant intrinsic defects in CuCrO2; among these intrinsic defects, Vcu is the most efficient acceptor in CuCrO2. It is found that all the donor-type extrinsic defects have difficulty in inducing n-conductivity in CuCrO2 because of their deep transition energy level. For all the acceptor-type extrinsic defects, substituting Mg for Cr is the most prominent doping aceeptor with relative shallow transition energy levels in CuCrO2. Our calculation results are expected to be a guide for preparing promising n-type and p-type materials in CuCrO2.展开更多
文摘研制开发新型的光电材料对促进社会经济发展具有重要的科学意义和实用价值.利用宽禁带CuInO_2铟基材料实现全透明光电材料是目前深入研究的热点.通过基于密度泛函的第一性原理计算方法,本文计算出掺杂元素Mg, Be, Mn在CuInO_2的形成能.计算结果表明,施主类缺陷(如掺杂元素替代Cu原子或进入间隙位置)由于较高的形成能和较深的跃迁能级,很难在CuInO_2材料中出现N型导电;而受主缺陷中,在氧原子化学势极大的情况下, Mg原子替代In能成为CuInO_2理想的受主缺陷.计算结果可为制备性能优异的CuInO_2材料提供指导.
文摘为研究碳表面对甲烷的吸附特性,采用基于密度泛函理论的第一性原理方法系统地研究了甲烷分子吸附在碳表面后的电子态密度、功函数和吸附能,同时研究了碳的表面能、层间弛豫与表面厚度之间的关系。计算结果表明,层间弛豫是由于相邻层间的弱相互作用引起的;顶位是甲烷最稳定的吸附部位;甲烷的吸附位置位于碳的碳原子上方3.21处,吸附能为-0.133 e V,与碳表面厚度关系不大;因少量电荷从碳表面转移到甲烷分子,甲烷吸附会使功函数略有增强。
基金Project supported by the National Natural Science Foundation of China (Grant No. 11147195)the Science Fund from the Guangxi Experiment Centre of Science and Technology (Grant No. LGZXKF201204)the Science Plan Projects of the Education Department of Guangxi Zhuang Autonomous Region (Grant No. 200103YB102)
文摘Using the first-principles methods, we study the formation energetics properties of intrinsic defects, and the charge doping properties of extrinsic defects in transparent conducting oxides CuCrO2. Intrinsic defects, some typical acceptortype, and donor-type extrinsic defects in their relevant charge state are considered. By systematically calculating the formation energies and transition energy, the results of calculation show that, Vcu, Oi, and Ocu are the relevant intrinsic defects in CuCrO2; among these intrinsic defects, Vcu is the most efficient acceptor in CuCrO2. It is found that all the donor-type extrinsic defects have difficulty in inducing n-conductivity in CuCrO2 because of their deep transition energy level. For all the acceptor-type extrinsic defects, substituting Mg for Cr is the most prominent doping aceeptor with relative shallow transition energy levels in CuCrO2. Our calculation results are expected to be a guide for preparing promising n-type and p-type materials in CuCrO2.
