Nishioka D, Tsuchiya T, Namiki W, Takayanagi M, Kawamura K, Fujita T, Yukawa R, Horiba K, Kumigashira H, Higuchi T
Department of Applied Physics, Tokyo University of Science, Katsushika, Tokyo, 125-8585, Japan.
International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), Tsukuba, Ibaraki, 305-0044, Japan.
Nanoscale Res Lett. 2020 Feb 17;15(1):42. doi: 10.1186/s11671-020-3267-5.
Sm-doped CeO (CeSmO; SDC) thin films were prepared on AlO (0001) substrates by radio frequency magnetron sputtering. The prepared thin films were preferentially grown along the [111] direction, with the spacing of the (111) plane (d) expanded by 2.6% to compensate for a lattice mismatch against the substrate. The wet-annealed SDC thin film, with the reduced d value, exhibited surface protonic conduction in the low-temperature region below 100 °C. The O1s photoemission spectrum exhibits HO and OH peaks on the SDC surface. These results indicate the presence of physisorbed water layers and the generation of protons on the SDC (111) surface with oxygen vacancies. The protons generated on the SDC surface were conducted through a physisorbed water layer by the Grotthuss mechanism.
通过射频磁控溅射在Al₂O₃(0001)衬底上制备了Sm掺杂的CeO₂(Ce₀.₉Sm₀.₁O₂; SDC)薄膜。制备的薄膜优先沿[111]方向生长，(111)面间距(d)扩大了2.6%，以补偿与衬底的晶格失配。经湿退火的SDC薄膜，其d值减小，在低于100°C的低温区域表现出表面质子传导。O1s光电子能谱在SDC表面呈现出H₂O和OH峰。这些结果表明在具有氧空位的SDC(111)表面存在物理吸附的水层并产生了质子。SDC表面产生的质子通过Grotthuss机制通过物理吸附的水层进行传导。
