Evaluation of Raman spectroscopy to detect fullerenes in geological materials

Fullerene C60 was determined repeatedly from a few types of carbonaceous matter from geological environments. Detailed investigation of structural aspects of pure carbonaceous matrices as well as of their experimental mixtures with fullerene C60 permits better understanding of the occurrence mode of fullerenes inside the network of natural samples. However, it appears that Raman microspectrometry is not competitive in the case of investigated current geological carbonaceous matrices with added fullerenes, when the concentration of fullerene C60 is 100 ppm or lower. In such a situation, C60 is highly dispersed and careful interpretation of the results of Raman microspectrometry does not permit us to obtain valuable quantitative structural data. Obtained sensitivity for detecting C60 in investigated matrices was only 1%. Analytical reasons for these results are discussed.