UAE Neem Extract as a Corrosion Inhibitor for Carbon Steel in HCl Solution

Table 2

Tafel corrosion currents and percentage inhibitions of the aqueous extract of Neem leaves at various concentrations in 1.0 M HCl at room temperature.

	1.0 M HCl	1.0 M HCl + 0.20 g/LExtract of Neem	1.0 M HCl + 0.50 g/LExtract of Neem	1.0 M HCl + 1.00 g/LExtract of Neem	1.0 M HCl + 2.00 g/LExtract of Neem
𝐸rest/V versus SCE	−0.465	−0.438	−0.433	−0.472	−0.583
𝑏𝑎/(mV/dec.)	57.5	61.1	94.5	112.0	143.9
𝑏𝑎/(mV/dec.)	63.8	56.1	87.7	77.2	76.1
𝐼“corrosion”/mA	0.76	0.237	0.169	0.151	0.101
PercentInhibition	—	68.82	77.76	80.13	86.84