Concentration

(mg∙L−1)

Rs

(Ω cm2)

Rp

(Ω cm2)

CPE

(Fs−(1−n) cm−2)

n

Cdl

(μF cm−2)

ηE

(%)

−0.3 [V vs. SCE]

0 HEDP

7.96

4.34 × 103

4.10 × 10−4

0.780

81.5

--

20 HEDP

6.29

6.20 × 103

3.20 × 10−4

0.810

74.6

30.0

30 HEDP

7.83

5.89 × 103

2.34 × 10−4

0.800

48.4

26.3

50 HEDP

14.5

6.91 × 103

1.54 × 10−4

0.790

30.4

37.2

100 HEDP

13.4

7.73 × 103

2.10 × 10−4

0.780

40.0

43.8

50 HEDP + 10 Ca2+

8.11

7.45 × 103

2.50 × 10−4

0.840

76.7

41.7

50 HEDP + 20 Ca2+

22.1

6.05 × 103

2.54 × 10−4

0.780

58.8

28.3

50 HEDP + 30 Ca2+

7.69

4.55 × 103

3.47 × 10−4

0.761

53.9

4.61

50 HEDP + 10 Zn2+

6.74

4.89 × 103

2.96 × 10−4

0.810

68.8

11.2

50 HEDP + 20 Zn2+

8.84

5.72 × 103

2.84 × 10−4

0.850

98.7

24.1

50 HEDP + 30 Zn2+

21.1

5.00 × 103

3.95 × 10−4

0.763

89.2

13.2

50 HEDP + 10 Mg2+

9.72

6.04 × 103

2.14 × 10−4

0.830

60.4

28.1

50 HEDP + 20 Mg2+

9.96

4.94 × 103

2.70 × 10−4

0.830

80.3

12.1

50 HEDP + 30 Mg2+

7.04

5.82 × 103

3.51 × 10−4

0.790

71.1

25.4

Ecorr [V vs. SCE]

0 HEDP

7.95

5.64 × 103

3.21 × 10−4

0.790

65.6

--

20 HEDP

7.32

7.57 × 103

1.17 × 10−4

0.850

33.6

25.5

30 HEDP

7.68

8.77 × 103

1.10 × 10−4

0.860

34.7

35.7

50 HEDP

10.1

8.80 × 103

2.05 × 10−4

0.840

63.2

35.9

100 HEDP

13.3

8.23 × 103

1.56 × 10−4

0.780

27.3

31.5

50 HEDP + 10 Ca2+

8.01

9.52 × 103

1.18 × 10−4

0.880

45.6

40.7

50 HEDP + 20 Ca2+

21.0

8.89 × 103

9.56 × 10−5

0.840

29.3

36.5

50 HEDP + 30 Ca2+

7.55

8.59 × 103

1.35 × 10−4

0.810

26.8

34.3

50 HEDP + 10 Zn2+

6.67

8.80 × 103

1.26 × 10−4

0.850

36.1

35.9

50 HEDP + 20 Zn2+

9.58

8.90 × 103

1.61 × 10−4

0.880

66.5

36.6

50 HEDP + 30 Zn2+

20.4

7.62 × 103

2.65 × 10−4

0.800

71.8

26.0

50 HEDP + 10 Mg2+

9.74

9.22 × 103

9.55 × 10−5

0.880

36.9

38.8

50 HEDP + 20 Mg2+

9.94

8.67 × 103

1.15 × 10−4

0.880

45.6

34.9

50 HEDP + 30 Mg2+

7.04

7.89 × 103

2.29 × 10−4

0.810

50.7

28.5

0.1 [V vs. SCE]

0 HEDP

8.97

6.12 × 103

1.00 × 10−4

0.820

21.4

--