AI 中文总结
本研究结合高分辨率氧K边XAS与从头算模拟、高通量筛选，建立了降解电池材料的计算解释途径，明确了NCM-811降解产物光谱差异的来源。
AI 中文摘要
锂离子电池中LiNi₀.₈Co₀.₁Mn₀.₁O₂（NCM-811）的降解会生成复杂的过渡金属氧化物和二元相，从根本上限制了正极性能。尽管通过X射线吸收光谱（XAS）识别这些降解产物对于缓解电化学性能损失至关重要，但由于实际样品的结构复杂性，解释工作仍具挑战性。本研究提出了一种结合高分辨率氧K边XAS与基于多体微扰理论的从头算模拟、以及基于密度泛函理论的高通量筛选的集成理论-实验框架。我们首先评估了8种层状、尖晶石和名义岩盐型参考氧化物的光谱指纹，确定了理想单晶体相与实验光谱之间的差异。利用高通量筛选分析38种不同晶型的NiO、CoO和MnO的氧p投影态密度，我们提出光谱差异可由局部变化的结构集合（此处以简化结构代理表示）等因素产生。本研究为解释降解电池材料的复杂体系建立了可行且严谨的计算途径。
英文摘要
The degradation of LiNi$_{0.8}$Co$_{0.1}$Mn$_{0.1}$O$_2$ (NCM-811) in Li-ion batteries produces complex transition-metal oxides and binary phases that fundamentally limit cathode performance. While identifying these degradation products via X-ray absorption spectroscopy (XAS) is essential for mitigating electrochemical performance loss, interpretation remains challenging due to the structural complexity of real-world samples. In this work, we present an integrated theoretical-experimental framework combining high-resolution oxygen K-edge XAS with \textit{ab initio} simulations based on many-body perturbation theory and high-throughput screening from density functional theory. We first evaluate the spectroscopic fingerprints of eight layered, spinel, and nominal rock-salt reference oxides, identifying discrepancies between the idealized single-crystal bulk phase and experimental spectra. Using high-throughput screening to analyze the oxygen $p$-projected density of states of 38 distinct polymorphs of NiO, CoO, and MnO, we propose that the spectral differences can emerge, among other factors, from a structural ensemble of local variations represented here by simplified structural proxies. Our work establishes a viable and rigorous computational pathway to interpret the complex landscape of degraded battery materials.
