Table 6. Chemical Composition Obtained by XPS from the API 5L X60 Steel Surface after 4 h of Immersion in 1M H₂SO₄ in the Presence of PILs.

	chemical composition (at. %)
sample	Fe 2p	O 1s	S 2p	N 1s	C 1s
blank	6.48	68.52	15.48	-	9.52
poly[VIMC4][Im]	2.71	31.20	3.41	4.34	58.34
poly[VIMC2][Br]	8.66	46.25	3.50	4.09	37.50
poly[VIMC4][Br]	14.22	48.65	4.46	2.00	30.67