Impedance parameters for all the studied inhibitors on MS in 1 M HCl medium.

Inhibitor	Conc. (ppm)	R s (Ω)	R ct (Ω)	n	CPE (μF cm−2)	IE (%)
—	0	1.345	40.53	0.9550	939.8	—
CNHE	10	2.997	42.11	0.7552	822.50	3.75
	100	2.228	54.82	0.6235	735.40	26.06
	200	2.115	66.82	0.7070	722.16	39.34
	500	2.445	85.34	0.7100	601.45	52.50
	1000	2.205	83.70	0.6485	630.42	51.57
CNDE	10	2.299	114.6	0.7480	785.12	64.63
	100	2.682	201.7	0.8422	528.68	79.09
	200	2.107	296.5	0.8826	415.54	86.33
	500	2.702	453.0	0.8248	249.73	91.05
	1000	2.737	400.0	0.8375	360.80	89.86
CNME	10	2.228	58.38	0.8602	810.57	30.57
	100	2.238	188.60	0.8522	659.27	78.51
	200	2.150	268.12	0.7562	509.21	84.88
	500	2.680	326.50	0.9210	454.83	87.58
	1000	2.465	301.20	0.8960	472.60	86.54
1	100	2.895	86.2	0.741	628.4	52.98
	200	2.924	129.3	0.792	534.05	68.65
	500	2.735	181.7	0.874	412.6	77.70
	1000	2.697	277.5	0.890	258.4	85.40
2	100	2.740	77.8	0.810	623.6	47.90
	200	2.723	104.3	0.594	600.5	61.14
	500	2.682	195.6	0.599	496.3	79.27
	1000	2.056	338.7	0.602	188.4	88.05
3	100	2.890	77.1	0.543	771.2	47.46
	200	2.772	129.4	0.768	569.4	68.67
	500	2.769	184.7	0.681	395.4	78.05
	1000	2.766	268.6	0.630	265.3	82.91