单壁纳米碳管的纯化及其储氢特性

针对半连续氢电弧法制备的单壁纳米碳管提出了一种纯化方法。采用HNO3和H2O2回流水煮的方法对单壁纳米碳管进行了纯化处理，透射电镜观察及热重分析表明样品中的无定形炭、纳米碳颗粒及金属催化剂颗粒等杂质可被有效去除，提纯后单壁纳米碳管的收率约为35％，纯度在95％以上；研究发现该纯化方法对单壁纳米碳管的孔径分布和比表面积有较大影响。采用体积法测定了纯化前后单壁纳米碳管样品的储氢容量，结果表明纯化样品的储氢量为1．65％，比未提纯样品（0．56％）有较大提高。

PURIFICATION AND HYDROGEN ADSORPTION OF SINGLE- WALLED CARBON NANOTUBES

The purification of single-walled carbon nanotubes(SWNTs)synthesized by a hydrogen arc-discharge method was investigated.After treated by using a HNO3 and H2O2 reflux method,the impurities of amorphous carbon,carbon nanoparticles and metal catalysts that initially co-existed with the as-prepared SWNTs were removed effectively.Based on the results of electron microscopy observations and thermo-gravimetric analysis,the purity of the purified sample was estimated to be above 95% at a yield of about 35%.The effect of the H2O2 reflux treatment on the pore structure of the purified SWNTs was studied.It is shown that the pore distribution and specific surface area of the SWNTs can be significantly influenced by the purification process.The hydrogen adsorption property of the SWNTs was investigated by using a volumetric testing method.The hydrogen storage capacity of the purified SWNTs was 1.65%,evidently higher than that(0.56%)of the as-prepared SWNTs sample.