Graphene-based cones with nanosized apex can be obtained by means of a high temperature pyrolytic carbon deposition process using methane and hydrogen as gaseous feedstock and single carbon nanotubes as deposition substrates. Aside the cones, micrometer-sized carbon beads or fibre segments are deposited meanwhile which are a key morphological component for allowing handling and mounting the carbon cones and then using them for various applications. Based on both the literature dealing with pyrolytic carbon deposition processes and experimental observations, a peculiar deposition mechanism is proposed, involving the transient formation of pitch-like liquid phase droplets which deposit onto the individual carbon nanotubes. In this picture, it is believed that a key parameter is the diameter ratio for the droplets and the nanotubes, respectively. The cone concentric texture and perfect nanotexture are shown by high resolution transmission electron microscopy, which allows interesting mechanical and conducting properties to be predicted. Correspondingly, applications of the carbon nanocones as electron emitters for cold-field electron sources on the one hand, and as probes for various modes of near-field microscopy on the other hand, have been tested.

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碳纳米管负载的热解碳纳米锥的合成及（一些）应用

具有纳米级顶点的基于石墨烯的锥体可以通过高温热解碳沉积工艺来获得，该沉积工艺使用甲烷和氢气作为气态原料并且使用单个碳纳米管作为沉积基质。除锥体外，同时还沉积了微米级尺寸的碳珠或纤维段，这是允许处理和安装碳锥体然后用于各种应用的关键形态成分。基于涉及热解碳沉积过程的文献和实验观察，提出了一种独特的沉积机理，涉及瞬态形成沥青状液相液滴，该液滴沉积在各个碳纳米管上。在该图中，认为关键参数分别是液滴和纳米管的直径比。高分辨率的透射电子显微镜显示了锥形同心织构和完美的纳米纹理，可以预测有趣的机械和导电性能。相应地，已经测试了碳纳米锥一方面用作冷场电子源的电子发射器，另一方面用作各种近场显微镜模式的探针的应用。