Correlated high resolution transmission electron microscopy and X-ray photoelectron spectroscopy studies of structured CNx (0 < x < 0.25) thin solid films
Correlated high resolution transmission electron microscopy and X-ray photoelectron spectroscopy studies of structured CNx (0 < x < 0.25) thin solid films
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DOI：
10.1016/j.carbon.2004.06.011
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发表时间：
2004
期刊：
影响因子：
10.9
通讯作者：
J. Neidhardt;L. Hultman;Z. Czigány
中科院分区：
文献类型：
--
作者：
J. Neidhardt;L. Hultman;Z. Czigány
结构化氮化碳（CNx），薄固体膜，也称为类富勒烯，在氮取代时由弯曲和交联的石墨烯平面组成。采用非平衡反应磁控溅射法合成了样品，并用高分辨透射电子显微镜（HRTEM）和X射线光电子能谱（XPS）对样品进行了分析。通过调节生长温度、放电气体中N2含量和离子能量等合成条件，可以控制薄膜的平面排列、延伸和交联等微观结构的演化。平面样品的高分辨透射电镜被用来检查依赖于生长温度和N2分数的结构变化。用于成像的结构特征的投影伪影的问题部分地克服了选定区域的电子衍射分析，其中它示出了对应于3.5 μ m的衍射与结构化CNx的形成相关联。N的掺入对于严重弯曲和频繁交联的基面的演变至关重要，因为与纯碳膜相比，它在低得多的能量下触发五边形形成和交联。因此，这两个光谱特征的氮1s核心电子光谱的XPS检查与微观结构的演变。
Structured carbon nitride (CNx), thin solid films, also known as fullerene-like, consist of, upon nitrogen substitution, bent and cross-linked graphene planes. They were synthesized by unbalanced reactive magnetron sputtering and analyzed by high-resolution transmission electron microscopy (HRTEM) in combination with X-ray photoelectron spectroscopy (XPS). The microstructure evolution in terms of plane alignment, extension and cross-linking can be controlled by adjusting the synthesis conditions, such as growth temperature, N2fraction in the discharge gas and ion energy. HRTEM on plan-view samples was used to examine the structural changes depending on growth temperature and N2fraction. The problem of projection artifacts for imaging the structural features was partially overcome by selected area electron diffraction analysis, where it is shown that diffraction corresponding to 3.5 Å is associated with the formation of structured CNx. The incorporation of N is crucial for the evolution of heavily bent and frequently cross-linked basal planes, since it triggers pentagon formation and cross-linking at much lower energies compared to pure carbon films. Therefore, the two spectral features in the nitrogen 1s core electron spectra as examined by XPS were correlated to the microstructure evolution.