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测量了定向石墨和纳米碳的正电子寿命谱。结果表明，热解法制备的纳米碳存在开空间小于单空位的自由体积以及开空间相当于约１０个空位聚集体的微孔洞。比较了热解法制备的纳米碳、ＵＦＰ冷压法制备的纳米Ｆｅ和纳米ＴｉＯ２以及非晶晶化法制备的纳米ＮｉＰ的缺陷结构特征，结果为纲米ＮｉＰ中缺陷的电子密度最高，纳米Ｆｅ和纳米ＴｉＯ２的次之，纳米碳的最低；纳米碳中的缺陷浓度最高，纳米Ｆｅ和纳米ＴｉＯ２的次之，纳米ＮｉＰ的最低。在纳米碳中没有观察到由多个晶粒围成的大孔洞
Positron lifetime spectra of oriented graphite and nanocarbon were measured. The results show that the carbon nanotubes prepared by pyrolysis have the free volume with open space less than single vacancy and the micropores with open space corresponding to about 10 vacancy aggregates. The defect structure characteristics of nano-carbon prepared by pyrolysis method, nano-Fe prepared by UFP cold pressing and nano-TiO2 and nano-NiP prepared by amorphous crystallization were compared. The results showed that the electron density of nano-NiM was the highest, And nano-TiO2 followed, the lowest nano-carbon; nano-carbon in the highest concentration of defects, followed by nano-Fe and nano-TiO2, nano-NiP the lowest. No large pores surrounded by multiple grains were observed in the nanocarbon