洋葱状富勒烯的CCVD法制备及其形貌特征

Morphology analysis of onion-like fullerenes prepared by CCVD

采用催化化学气相沉积法(CCVD)制备了洋葱状富勒烯 (OFs),借助高分辨透射电镜 (HRTEM)观察和分析了其形貌结构。结果发现,以负载Co2+的Y型沸石为催化剂,C2H2为碳源,反应温度为 700℃时,单位催化剂产炭率的质量分数为 66%,其中洋葱状富勒烯的收率可达产炭率体积分数的 20%以上;并认为OFs的生长机理为由内到外逐层石墨化的气固(VS)模式。

Onion-like fullerenes ( OFs) were prepared by catalytic chemical vapor deposition ( CCVD), and their morphologies and microstructure were characterized by high resolution transmission electron microscope. Results show that OFs can be obtained under the conditions where Co+2 supported by the zeolite ( NaY) was used as catalyst, and acetylene was used as carbonaceous gas with the reaction temperature controlled at 700 degrees C. The carbon yield per weight of catalyst can reach 60 % and the portion of OFs can reach above 20 %. From their vapor-solid formation pattern it is speculated, that graphitization occurs in successive stages from the core to the surface.