Table 2.

Atomic percentages of the oxygen functional groups on the surface of the carbon nanoparticles obtained by XPS.

Sample	Atomic %
	C-OH	C=O	O-C=O	Carbonate	C	O
GMC	12.21	8.12	2.40	3.40	99.60	0.40
GMCac	12.31	7.58	3.33	3.75	95.61	4.39
PMC	9.97	8.27	3.84	4.44	99.90	0.10
PMCac	16.74	11.99	10.62	4.47	82.10	17.90