近日，美国斯坦福大学Bent, Stacey F.团队研究了电池界面的低温x射线光电子能谱。2025年10月22日，《自然》杂志发表了这一成果。

了解原始界面的化学环境是电化学、材料科学和表面科学长期追求的目标。对锂阳极中的固体电解质界面（SEI）的实质性了解源于X射线光电子能谱（XPS）分析。然而，室温（RT）结合超高真空（UHV）可诱导XPS过程中反应和挥发，造成SEI发生显著演变。因此，亟需一种可稳定SEI的表征技术。

研究组开发了具有快速深度冷冻的低温（冷冻）-XPS，并演示了SEI的原位保存。他们发现了UHV中实质上不同的SEI组分和更厚的原始SEI，且没有RT相关的厚度减少和重要组分（包括LiF和Li₂O）的改变。这种对原始SEI成分的最新分析实现了不同电解质化学之间的性能关联。但最重要的是，研究组强调了在低温条件下研究敏感界面的必要性。

附：英文原文

Title: Cryogenic X-ray photoelectron spectroscopy for battery interfaces

Author: Shuchi, Sanzeeda Baig, DAcunto, Giulio, Sayavong, Philaphon, Oyakhire, Solomon T., Sanroman Gutierrez, Kenzie M., Risner-Jamtgaard, Juliet, Choi, Il Rok, Cui, Yi, Bent, Stacey F.

Issue&Volume: 2025-10-22

Abstract: Understanding the chemical environment of pristine interfaces is a long-sought goal in electrochemistry, materials science and surface science. A substantial understanding of one such interface, the solid electrolyte interphase (SEI) in lithium anodes, originates from X-ray photoelectron spectroscopy (XPS)1,2. However, room temperature (RT) combined with ultrahigh vacuum (UHV) can induce major SEI evolution from reactions and volatilization during XPS1,2. Thus, a technique is necessary for SEI stabilization. Here we develop cryogenic (cryo)-XPS with immediate plunge freezing and demonstrate SEI preservation. We discover substantially different SEI speciation and a thicker pristine SEI with cryo-XPS, free from RT-associated thickness reduction and alterations to important species, including LiF and Li2O, in UHV. This new access to pristine SEI composition enables performance correlations across diverse electrolyte chemistries. Primarily, we highlight the necessity of studying sensitive interfaces under cryogenic conditions.

DOI: 10.1038/s41586-025-09618-3

Source: https://www.nature.com/articles/s41586-025-09618-3