Study of structures at the boundary and defects in organic thin films of perchlorocoronene by high-resolution and analytical transmission electron microscopy
Study of structures at the boundary and defects in organic thin films of perchlorocoronene by high-resolution and analytical transmission electron microscopy
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DOI：
10.1016/j.ultramic.2010.09.003
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发表时间：
2010-11-01
期刊：
影响因子：
2.2
通讯作者：
Isoda, Seiij
中科院分区：
文献类型：
--
作者：
Koshino, Masanori;Kurata, Hiroki;Isoda, Seiij
用高分辨透射电子显微镜（HRTEM）、电子衍射（艾德）、电子能量损失谱（EELS）和能量过滤透射电子显微镜（EFTEM）表征了全氯蔻（C（24）Cl（12））晶体的周期和非周期结构。在C（24）Cl（12）晶体的边界处的HRTEM图像显示出缺陷结构的灵活性，其中分子排列以补偿两个不同畴之间的不连续性。通过过滤图像强调，发现非周期性区域在小电子束照射（类似于10（6）个电子nm（-2））的任何地方产生，然后在整个区域上扩散，以在更高的电子剂量（类似于2 × 10（6）个电子nm（-2））后完全破坏周期性结构。通过艾德、EELS和EFTEM监测电子束辐照的效果，其中周期性结构和含量元素在高达10（6）电子nm（-2）时得到很好的保留，但氯原子随着高得多的电子剂量而减少。这是解释的C-Cl键的断裂，分离氯原子，证实了能量损失附近的边缘结构（ELNES）的碳π * 峰和氯损失在边缘的试样，以及通过理论模拟。氯的脱离位于孔周围的外围边缘，这一点通过芯损EFTEM成像得到证实。(C)2010 Elsevier B. V.保留所有权利。
Both the periodic and non-periodic structures of perchlorocoronene (C(24)Cl(12)) crystals were characterized by high-resolution transmission electron microscopy (HRTEM), electron diffraction (ED), electron energy-loss spectroscopy (EELS), and energy-filtered transmission electron microscopy (EFTEM). The HRTEM images at the boundary of the C(24)Cl(12) crystals exhibit the flexibility of defect structures, where molecules align to compensate for the discontinuity between two different domains. Emphasized by the filtered images, it was found that the non-periodic regions are created everywhere with a small electron beam irradiation (similar to 10(6) electrons nm(-2)) and then spread over the entire regions to completely destroy the periodic structures after a higher electron dose (similar to 2 x 10(6) electrons nm(-2)). The effect of the electron beam irradiation was monitored by ED, EELS, and EFTEM, where periodic structures and content elements are well preserved up to 10(6) electrons nm(-2), but chlorine atoms decreased with a much higher electron dose. This is explained by the breakage of the C-Cl bond to detach chlorine atoms, confirmed by energy-loss near the edge structures (ELNES) of carbon pi* peaks and chlorine loss at the edge of the specimen, as well as by theoretical simulation. The detachment of chlorine is localized at the peripheral edge around a hole confirmed by core-loss EFTEM imaging. (C) 2010 Elsevier B.V. All rights reserved.