LiCl-KCl熔盐中纯氧氧化提纯单壁碳纳米管

Purification of Single-walled Carbon Nanotubes by Oxygen Oxidation in LiCl-KCl Molten Salt

以LiCl-KCl(wLiCl∶wKCl=55∶45)熔盐为反应介质,对在熔盐中纯氧氧化提纯单壁碳纳米管(SWCNT)进行了研究.发现可以通过控制熔盐温度和氧气流量来控制氧化反应温和地进行.将5gSWCNT粗产品分散在200g熔盐中,在470℃下用300mL?min-1氧气氧化2h可获得3.8%SWCNT收率.采用TEM,SEM,TGA和Raman谱对提纯前后SWCNT的形貌和组成进行了分析,发现提纯后SWCNT产品中无定形碳被有效去除,而SWCNT结构未发现明显变化.

The purification of SWCNT by oxygen oxidation in LiCl-KCl molten salt was investigated.5 g of as-prepared SWCNT was suspended in 200 g of molten salt（wLiCl∶wKCl=55∶45） at 470 ℃ by agitation.After 2 h oxidation in 300 mL·min-1 oxygen flow, 3.8% of purified SWCNT was obtained.The oxidation degree could be controlled by adjusting the reaction temperature and oxygen flow rate.Scanning electron microscopy（SEM）, transmission electron microscopy（TEM）, thermogravimetric analysis（TGA） and Raman spectra were employed to characterize the as-prepared and purified SWCNT.The results indicated that almost all of the amorphous carbon in as-prepared SWCNT was removed.However, the SWCNT can survive from this purification process.