Detailed information of XPS results.

Sample	Element	Group	BEa (eV)	FWHM (eV)	Area (P) CPS.eV	Ref.
UN	C 1s	C–C	284.8	1.875	30 531.710	46
	O 1s	O–Si–O	532.7	1.600	40 251.900	47
DP	C 1s	C–C	284.8	1.300	12 590.720	48 and 49
		C–O/C–N	285.6	2.120	32 423.630
		C O	287.7	1.730	5273.321
	N 1s	R–NH2	399.5	2.500	4524.323	50–52
		C–N	400.2	1.700	2348.640
	O 1s	C O	531.0	1.600	4165.241	47
		O–Si–O/C–O	532.7	2.400	34 449.830

^aBE: binding energy.