当前位置: X-MOL 学术Surf. Sci. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
LiOx-modification of Ni and Co3O4 surfaces: An XPS, LEIS and LEED study
Surface Science ( IF 1.9 ) Pub Date : 2021-08-02 , DOI: 10.1016/j.susc.2021.121915
Thomas Haunold 1 , Günther Rupprechter 1
Affiliation  

LiOx was deposited at room temperature by physical vapor deposition (PVD) on polycrystalline Ni foil and Co3O4(111) thin film, creating uniform model systems well-suited for surface-sensitive characterization by X-ray photoelectron spectroscopy (XPS), low energy ion scattering (LEIS) or low energy electron diffraction (LEED). In the case of Ni, about 15 layers of LiOx film were grown under the current conditions either stepwise or continuously, with XPS analysis indicating a deposition rate of 0.16 and 0.24 ML/min, respectively. Li 1s and O 1s spectra revealed that Li2O and to a lesser extent LiOH were preferentially formed. The stability of the LiOx films was examined in UHV, upon annealing at 573 K and upon hydrogen reduction at 723 K. On the more reactive Co3O4(111) film grown on Ir(100), the Li accommodation rate was about twice as high, at least within the first minutes of deposition. Post-deposition LEED showed an obscured cobalt oxide diffraction pattern, not unexpected in light of the LiOx deposited. On both substrates, LEIS characterization of Li (≈ 103 eV) was prevented by the high background in this kinetic energy region, due to surface roughness and unspecific scattering. Still, LiOx deposition was evident from the vanished LEIS signals of Ni or Co. The prepared LiOx-modified surfaces may serve as starting point for the future growth of epitaxial LixCoO2 model systems.



中文翻译:

Ni 和 Co3O4 表面的 LiOx 改性:XPS、LEIS 和 LEED 研究

LiO x在室温下通过物理气相沉积 (PVD) 沉积在多晶 Ni 箔和 Co 3 O 4 (111) 薄膜上,创建了非常适合通过 X 射线光电子能谱 (XPS) 进行表面敏感表征的均匀模型系统、低能离子散射 (LEIS) 或低能电子衍射 (LEED)。在 Ni 的情况下,在当前条件下逐步或连续生长约 15 层 LiO x膜,XPS 分析表明沉积速率分别为 0.16 和 0.24 ML/min。Li 1s 和O 1s 光谱显示优先形成Li 2 O 和少量LiOH。LiO x的稳定性在 UHV 中检查薄膜,在 573 K 下退火并在 723 K 下氢还原。在Ir(100) 上生长的反应性更强的 Co 3 O 4 (111) 薄膜上,Li 容纳率大约高两倍,至少在沉积的第一分钟内。沉积后的 LEED 显示出模糊的氧化钴衍射图案,鉴于沉积的 LiO x并不意外。在两个基板上,由于表面粗糙度和非特异性散射,该动能区域的高背景阻止了 Li (≈ 103 eV) 的 LEIS 表征。尽管如此,从 Ni 或 Co 消失的 LEIS 信号可以明显看出LiO x沉积。制备的 LiO x-改性表面可以作为外延Li x CoO 2模型系统未来生长的起点。

更新日期:2021-08-10
down
wechat
bug