Abstract A simple and effective way to manufacture graphene from a coal tar pitch (CTP) is demonstrated. Silica (SiO 2 ) nanoparticles were used to modify the CTP as carbon precursor. A silica nanofiller introduced into the CTP matrix underwent carboreduction during heat treatment to 2000 °C, resulting in the formation of silicon carbide. Surfaces of SiC grains were sites for graphene formation. The influence of SiO 2 on the structure and microstructure of CTP- based carbon matrix, after annealing up to 2800 °C, was studied. Carbon samples were analyzed using X- ray Diffraction (XRD), Transmission Electron Microscopy (TEM) and Raman Spectroscopy. Crystallite sizes (L a , L c ) and interplanar distance (d 002 ) were determined. The presence of SiO 2 in CTP carbon precursor favored the crystallites’ growth in the ‘a′ crystallographic graphite direction, and inhibited their growth on the ‘c′ axis. The crystallites composing of graphene layers, were characterized by an elongated dimension in the ‘a′ axis direction. Above 2000 °C silicon carbide decomposed, followed by the sublimation of silicon from the carbon matrix.

中文翻译：

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SiO 2 纳米颗粒存在下煤焦油沥青衍生的碳结构中催化石墨烯的形成

摘要 展示了一种从煤焦油沥青 (CTP) 制造石墨烯的简单有效方法。二氧化硅（SiO 2 ）纳米颗粒被用来修饰作为碳前体的CTP。引入到 CTP 基体中的二氧化硅纳米填料在热处理至 2000°C 的过程中经历了碳化反应，从而形成了碳化硅。SiC 晶粒的表面是石墨烯形成的场所。研究了 SiO 2 对 CTP 基碳基体结构和微观结构的影响，在退火至 2800 °C 后，进行了研究。使用 X 射线衍射 (XRD)、透射电子显微镜 (TEM) 和拉曼光谱分析碳样品。确定微晶尺寸（L a ，L c ）和晶面间距（d 002 ）。CTP碳前驱体中SiO 2 的存在有利于微晶在'a'结晶石墨方向上的生长，并抑制它们在'c'轴上的生长。由石墨烯层组成的微晶的特征在​​于'a'轴方向上的拉长尺寸。高于 2000 °C 时，碳化硅分解，随后硅从碳基体中升华。