Protonic Conduction in La2NiO4+delta and La2-xAxNiO4+delta (A = Ca, Sr, Ba) Ruddlesden-Popper Type Oxides
Protonic Conduction in La2NiO4+delta and La2-xAxNiO4+delta (A = Ca, Sr, Ba) Ruddlesden-Popper Type Oxides
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La2NiO4 delta 和 La2-xAxNiO4 delta (A = Ca, Sr, Ba) Ruddlesden-Popper 型氧化物中的质子传导
DOI：
10.1002/aenm.202200392
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发表时间：
2022
期刊：
影响因子：
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通讯作者：
Truls Norby,* and Donglin Han*
中科院分区：
文献类型：
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作者：
Peng Zhong;Kazuaki Toyoura,* Lulu Jiang;Lubing Chen;Sara Adeeba Ismail;Naoyuki Hatada;Truls Norby,* and Donglin Han*
La2NiO4+δ基Ruddlesden-Popper （RP）氧化物具有显著的水化和质子传导特性，可作为质子陶瓷电化学电池（PCECs）的正极材料。与钙钛矿电解质和正极材料不同，质子驻留并跳跃在常规氧化离子上，RP氧化物如La2NiO4+δ可能含有氧间隙，并提供了质子定位和迁移的可能性，这表明正极可能通过三重传导运作。这里，理论计算支持质子通过钙钛矿层中的非共享氧化物离子在岩盐层中的间隙氧化物离子之间迁移。此外，还报道了原始La2NiO4+δ和La2‐xAxNiO4+δ(A= Ca, Sr, Ba)的含水量，表明水化作用随着掺杂水平和碱度的增加而增加。Hebb - Wagner阻断电极测量在所有样品中显示出显著的部分质子电导率。掺杂对水化和p型电导率的影响表明，质子主要存在于结构氧化离子上，但在氧过量的情况下，不能排除间隙氧化离子对质子溶解和迁移的作用。研究结果对RP氧化物作为pcec正极材料的进一步研究和优化具有指导意义。
A significant hydration and protonic conduction in La2NiO4+δ‐based Ruddlesden–Popper (RP) oxides will enable their use as positrode materials in proton ceramic electrochemical cells (PCECs). Unlike perovskite electrolytes and positrode materials, where protons reside and jump on regular oxide ions, RP oxides such as La2NiO4+δmay contain oxygen interstitials and offer the possibility that protons locate on and migrate by help of these, suggesting a mechanism by which positrodes may operate by triple conduction. Here, theoretical calculations that support proton migration between interstitial oxide ions in the rock‐salt layer via unshared oxide ions in the perovskite layer are reported. Furthermore, water contents of pristine La2NiO4+δand La2‐xAxNiO4+δ(A= Ca, Sr, Ba) are reported, showing that hydration increases with the level and basicity of the dopant. Hebb‐Wagner blocking electrode measurements show significant partial protonic conductivity in all samples. The effects of doping on hydration and ofon the p‐type conductivity suggest that protons reside primarily on structural oxide ion, but a role of interstitial oxide ions for dissolution and migration of protons cannot be ruled out in cases with oxygen excess. The results are instructive for further studies and optimization of RP oxides as potential positrode materials for PCECs.