洋葱状富勒烯的提纯研究

以石墨粉为碳源, Al为催化剂, 采用真空热处理法制备了平均粒径为15～35 nm的洋葱状富勒烯(OLFs).并用CS₂分离和空气氧化法对得到的OLFs初产品进行了提纯处理.高分辨透射电镜(HRTEM)、X射线衍射(XRD)、热重分析(TGA)对提纯前后样品的分析表明, CS₂分离处理可有效去除初产品中裸露的金属催化剂微粒,然后在空气中610 ℃焙烧200 min,可基本去除无定型碳,并大量去除了石墨状碎片等碳杂质, OLFs的纯度在50％(体积分数)以上.

Study on the Purification of Onion-like Fullerenes

Onion-like fullerenes(OLFs) with an external diameter between 15 nm and 35 nm were prepared by vacuum heat-treatment methods of graphite powers using Al as catalyst. Resultant OLFs were purified by removing impurities using CS₂ treatment and air oxidation method. HRTEM, XRD and TGA are applied to analysize samples before and after purification. The results indicate that CS₂ treatment can effectively remove metal catalyst particles. After the succeeding calcination at 610 ℃ for 200 min in air, most of amorphous carbon and graphite pieces are removed, the purity of the OLFs is above 50％(volume ratio).