Can we determine the activation energy for ionic conduction from the nuclear- and electron-density distributions?

我们可以根据核密度和电子密度分布确定离子传导的活化能吗？

• 批准号: 23655190
• 负责人: YASHIMA Masatomo
• 金额: $ 2.66万
• 依托单位: Tokyo Institute of Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Challenging Exploratory Research
• 财政年份: 2011
• 资助国家: 日本
• 起止时间: 2011 至 2012
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-23655190/
• 关键词: イオン交換体; 伝導体; 活性化エネルギー; イオン伝導

In this project, we have investigated the crystal structure, nuclear-density distribution, electronic structure and oxygen permeation rate of two K_2NiF_4-type oxides of Pr_2(Ni_0.75Cu_0.25)_0.95Ga_0.05O_4+δ and Pr_2Ni_0.75Cu_0.25_O4+δ. Nuclear-density distributions of Pr_2(Ni_0.75Cu_0.25)_0.95Ga_0.05O_4+δ and Pr_2Ni_0.75 Cu_0.25_O4+δ at high temperatures have visualized the -(apical oxygen O2)- (interstitial oxygen O3)-(apical oxygen O2)- diffusional pathway of oxide ions, which indicates an interstitialcy diffusion mechanism. It was found that the minimum nuclear density on the O2-O3 pathway ρN(T) is a useful microscopic parameter for the oxygen diffusivity. The ρN(T) is regarded as the oxygen probability density at the bottleneck for diffusion. The oxygen permeation rate ρp (T) increases with an increase of ρN (T). The activation energy for oxygen diffusion estimated by the plots of log(the normalized oxygen permeation rate ρP (T)/δ ) against T^-1 (reciprocal of absolute temperature) is independent of temperature, as well as the formation energy of oxygen atoms at the bottleneck from the plots of log(ρN(T)/ δ ) against T^-1. These results indicate that the amount of interstitial oxygen δ is proportional to the carrier concentration for the oxide-ion diffusion.

本课题研究了Pr_2(Ni_0.75Cu_0.25)_0.95Ga_0.05O_4+δ和Pr_2Ni_0.75Cu_0.25_O4+δ两种k_2nif_4型氧化物的晶体结构、核密度分布、电子结构和氧渗透速率。高温下Pr_2(Ni_0.75Cu_0.25)_0.95Ga_0.05O_4+δ和Pr_2Ni_0.75 Cu_0.25_O4+δ的核密度分布显示了氧化物离子的-（尖氧O2）-（间隙氧O3）-（尖氧O2）-扩散途径，表明了间质扩散机制。发现O2-O3途径上的最小核密度ρN(T)是表征氧扩散率的一个有用的微观参数。ρN(T)作为扩散瓶颈处的氧概率密度。氧渗透速率ρp (T)随ρN (T)的增大而增大。由对数（归一化氧渗透速率ρP (T)/δ）对T^-1（绝对温度倒数）的曲线估计的氧扩散活化能与温度无关，以及由对数（ρN(T)/ δ）对T^-1的曲线估计的瓶颈处氧原子的形成能与温度无关。这些结果表明，间隙氧δ的量与氧离子扩散的载流子浓度成正比。

项目成果

Visualization of the Diffusional Pathway of Mobile Ions iIonic Conducting Ceramics through Diffraction Experiments

通过衍射实验可视化移动离子离子导电陶瓷的扩散路径

• 发表时间: 2012
• 作者: M. Yamagata;他;M.Yashima
• 通讯作者: M.Yashima

K2NiF4型混合伝導体Pr1.9NiO4+δの結晶構造変化

K2NiF4型混合导体Pr1.9NiO4+δ晶体结构变化

• 发表时间: 2012
• 作者: Y.Masubuchi;R.Yamaoka;T.Motohashi;K.Kirihara;W.Lee;K.Watanabe;T.Sekiguchi;S.Kikkawa;石川 正司;原武 大樹
• 通讯作者: 原武 大樹

K_2NiF_4型Pr_1.9NiO_4における酸化物イオンの拡散機構

K_2NiF_4型Pr_1.9NiO_4中氧离子的扩散机理

• 发表时间: 2013
• 作者: M. Ishikawa;他;八島正知・原武大樹・齋藤未央・藤井孝 太郎・Yi-Ching hen・Sirikanda Nuansaeng・石原達己
• 通讯作者: 八島正知・原武大樹・齋藤未央・藤井孝 太郎・Yi-Ching hen・Sirikanda Nuansaeng・石原達己

K2NiF4型Pr1.9NiO4における酸化物イオンの拡散機構

K2NiF4型Pr1.9NiO4中氧离子的扩散机理

• 发表时间: 2013
• 作者: 笠井 祐貴;他;原武大樹
• 通讯作者: 原武大樹

Experimental Visualization of Chemical Bonding and Structural Disorder in Hydroxyapatite through Charge and Nuclear-Density Analysis

• DOI: 10.1021/jp208746y
• 发表时间: 2011-11
• 期刊: Journal of Physical Chemistry C
• 影响因子: 3.7
• 作者: M. Yashima;Y. Yonehara;H. Fujimori