洋葱状富勒烯的提纯研究

Study on the Purification of Onion-like Fullerenes

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15～35nm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200min,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.

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 degrees C for 200 min in air, most of amorphous carbon and graphite pieces are removed, the purity of the OLFs is above 50% (volume ratio).