Acid Corrosion Inhibition of Steel by Lamotrigine

Table 2

Polarisation and impedance parameters for steel in 1.0 M HCl and 0.5 M H₂SO₄ in presence of different concentration of lamotrigine.

Corrosive; media	Polarisation						EIS
	Inhibitor concentration (mM)	𝐸corr versus SCE; (mV)	𝐼corr; (𝜇A cm^−2)	𝛽c (mV dec^−1)	𝛽a(mV dec^−1)	% 𝜂𝑝	(𝑅𝑝 Ω cm^2)	𝐶dl (𝜇F cm^−2)	% 𝜂𝑧
HCl	Blank	−0.484	170.0	126	86	—	112	62	—
	0.5	−0.460	43.2	112	76	74.5	418	27	73.2
	1.0	−0.469	11.4	102	151	93.2	1670	12	93.1
	2.5	−0.467	7.0	112	142	95.8	2941	8.8	96.2
	5.0	−0.460	5.1	112	107	97.0	3350	9.9	96.6
H2SO4	Blank	−0.489	155.6	123	88	—	72	71	—
	0.5	−0.480	49.2	115	77	68.3	222	56	67.5
	1.0	−0.478	30.4	94	65	80.4	590	22	87.5
	2.5	−0.459	20.3	114	134	86.9	1112	16	93.5
	5.0	−0.463	9.8	110	116	93.7	1602	10	95.5