[1] D Cao, Y Peng, L Wang et al. Minerals (Basel), 9, 617(2019).

[5] C Ferrari A, C Meyer J, V Scardaci et al. Physical Review Letters, 97, 187401(2006).

[6] L An, L Liu, P Tan et al. Physical Review B, 66, 245410(2002).

[7] A Eckmann, A Felten, A Mishchenko et al. Nano Letters, 12, 3925(2012).

[8] G Compagnini, G Foti, O Puglisi. Carbon, 35, 1793(1997).

[9] M Bustin R, V Ross J, N Rouzaud J. International Journal of Coal Geology, 28, 1(1995).

[10] C Ferrari A, J Robertson. Physical Review B, 61, 14095(2000).

[11] N Batchelder D, R Gilkes K W, S Sands H et al. Applied Physics Letters, 70, 1980(1997).

[12] T Frauenheim, G Jungnickel, T Köhler. Physical Review B, 52, 11837(1995).

[13] S Lannin J, P Lopinski G, I Merkulov V. Applied Physics Letters, 69, 3348(1996).

[14] L Koenig J, F Tuinstra. The Journal of Chemical Physics, 53, 1126(1970).

[15] K Li, Q Liu, M Rimmer S. International Journal of Coal Geology, 195, 267(2018).

[16] W Grogger, G Rantitsch, C Teichert et al. International Journal of Earth Sciences, 93, 959(2004).