依靠金属元素的电子能量损失谱（EELS）获得微观结构分析，是研究过渡金属氧化物（TMOs）在催化、储能和转换等反应机理的一种方法。然而，由于电子束能量不足，K壳层信号低，金属元素L壳层电子结构复杂，限制了对TMOs配位环境的分析。本文采用密度泛函理论（DFT）计算、傅里叶变换（FT）和小波变换（WT）来探讨氧化铁的K-边光谱中四个单独峰与微观结构信息（化学键和原子协调）。结果表明，峰幅比与Fe元素的价态呈线性相关，通过径向分布函数（RDF）得到的配位数与标准配位结构模型得到的配位数呈良好的线性相关。因此，可以通过EELS O K-edge光谱实现对微观结构中价态变化和原子配位的定量分析。本研究将EELS O K-edge光谱作为定量分析TMOs的价态和原子配位信息的有前景的途径，并为进行微观结构分析提供了有效的方法 通过EELS O K-edge光谱可以实现对微观结构中价态变化和原子配位的定量分析。本研究将EELS O K-edge光谱作为定量分析TMOs的价态和原子配位信息的有前景的途径，并为进行微观结构分析提供了有效的方法 通过EELS O K-edge光谱可以实现对微观结构中价态变化和原子配位的定量分析。本研究将EELS O K-edge光谱作为定量分析TMOs的价态和原子配位信息的有前景的途径，并为进行微观结构分析提供了有效的方法通过非金属元素的EELS光谱。

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Relying on the electron energy loss spectrum (EELS) of metallic elements to obtain microstructure analysis is an investigation method of the reaction mechanisms of transition metal oxides (TMOs) in catalysis, energy storage and conversion. However, the low signal from K shell owing to insufficient electron beam energy, and the complicated electronic structure in L shell of the metal element restrict the analysis of the coordination environment of the TMOs. Herein, density functional theory (DFT) calculation, Fourier transform (FT) and wavelet transform (WT) were employed to probe the relationship between the four individual peaks in O K-edge spectra of iron oxides and the microstructure information (chemical bonds and atomic coordination). The findings show that the peak amplitude ration is in a linear correlation with the valence state of Fe element, and that the coordination number obtained by radial distribution function (RDF) is favorably linearly correlative with that from the standard coordination structure model. As a result, the quantitative analysis on the change of valence state and atomic coordination in microstructure can be realized by EELS O K-edge spectra. This study establishes EELS O K-edge spectrum as a promising pathway to quantitatively analyze the valence state and atomic coordination information of TMOs, and offers an effective method to conduct microstructure analysis via the EELS spectra of the non-metal element.