Energetics of Hydrogen States in SrZrO3
Energetics of Hydrogen States in SrZrO3
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SrZrO3 中氢态的能量
DOI：
10.2320/matertrans.43.1444
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发表时间：
2002
影响因子：
1.2
通讯作者：
H. Adachi
中科院分区：
文献类型：
--
作者：
M. Yoshino;Y. Liu;K. Tatsumi;I. Tanaka;M. Morinaga;H. Adachi
采用密度泛函理论在广义梯度近似下计算了氢在钙钛矿型氧化物SrZrO 3中的优化几何构型和形成能。在氧化物中的稳定的氢网站检查与特殊的利益。结果表明，氢与氧离子紧密结合，并位于SrZrO 3中ZrO 6八面体的稍微外侧。O-H键朝向第二近邻的氧离子，这引起相邻氧离子的大的局部位移。例如，最近邻的氧离子倾向于接近氢。添加受体掺杂剂钇，修改氢周围的氧离子的这种局部畸变，以增加质子导电性。此外，计算的氢形成能表明，氢的行为作为一个浅施主在SrZrO 3。从能量学的角度给出了质子导电氧化物掺杂和气氛控制的基本原理。
The optimized geometries and formation energies of hydrogen in the perovskite-type oxide, SrZrO3, have been calculated using the density functional theory under the generalized gradient approximation (GGA). The stable hydrogen sites in the oxide are examined with special interests. It is shown that the hydrogen is tightly bound to an oxygen ion and located slightly outside the ZrO 6 octahedron in SrZrO3. The O–H bond orientates towards the second-nearest-neighbor oxygen ion, which induces large local displacements of adjacent oxygen ions. For example, the nearest-neighbor oxygen ions tend to approach the hydrogen. The addition of an acceptor dopant, yttrium, modifies such local distortion of oxygen ions around the hydrogen as to increase protonic conductivity. In addition, the calculated hydrogen formation energy shows that the hydrogen behaves as a shallow donor in SrZrO3. The fundamental principles of doping and atmosphere control in proton conducting oxides are also given in view of energetics.