乙炔火焰无催化剂制备石墨烯片及生长机理研究（英文）

Growth of graphene sheets under an oxyacetylene flame without a catalyst

采用无催化剂乙炔火焰合成法在碳化钨基板上制备出石墨烯片,所制备的石墨烯片呈花瓣状均匀地垂直生长在副产物-炭微粒上,呈现出花状形貌。实验过程中,乙炔剧烈燃烧产生高温及高压环境,加速了未完全燃烧乙炔的裂解及自由碳基团的环化反应,直接在气相环境中合成了石墨烯微晶片,部分石墨烯微晶片会卷曲成炭黑晶核,炭黑晶核会继续吸附石墨烯微晶片生长为炭微粒。但是,在反应装置的作用下,携带石墨烯微晶片以及炭黑晶核的燃气流会在基体表面形成湍流和逆流,打乱了石墨烯晶片被炭黑粒子吸附并包裹使之生长的过程,导致石墨烯微晶片垂直于炭微粒生长为花瓣状石墨烯片。

High quality graphene sheets that had a lowI_D/I_G and a high 2D intensity in Raman spectra were prepared by a catalyst-free acetylene flame method. The sheets were grown vertically on the surface of carbon particles to form a petal-like morphology. A high temperature,high pressure and short residence time of the flame intensified the decomposition and cyclization reactions of acetylene,leading to the formation of graphene sheets in the gas phase. The turbulent flame and the gases released during the formation of the graphene sheets from carbon nuclei could be responsible for their petal-like morphology instead of an onion-like structure.