Preparation of Ti/SnO₂-Sb/Rare Earth Electrodes Containing Different Contents of Ni Intermediate Layer for Efficient Electrochemical Decolorization of Rhodamine B

Table 11

Energy per order of decolorized 20 mg·L⁻¹ RhB solution, evaluated from equation (5), and electrochemical decolorization of Ti/SnO₂-Sb-Ni/Re electrodes with various Ni contents and different rare earth elements in 200 ml dye solution.

Electrodes	kapp (min^−1)	Average voltage (V)	Energy (kW·h·m^−3·order^−1
Ni (0%)/Gd	0.0316	4.2	4.253
Ni (1%)/Gd	0.0554	4.2	2.426
Ni (2%)/Gd	0.2094	4.1	0.627
Ni (3.5%)/Gd	0.0366	4.1	3.585
Ni (5%)/Gd	0.0322	4	3.975
Ni (0%)/Ce	0.0476	4.1	2.756
Ni (1%)/Ce	0.0817	4.2	1.645
Ni (2%)/Ce	0.109	4.1	1.204
Ni (3.5%)/Ce	0.0409	4	3.129
Ni (5%)/Ce	0.0364	4	3.516
Ni (0%)/Eu	0.0539	4.2	2.494
Ni (1%)/Eu	0.0634	4.2	2.119
Ni (2%)/Eu	0.1727	4.1	0.759
Ni (3.5%)/Eu	0.0361	4.2	3.723
Ni (5%)/Eu	0.0084	4	15.238
Ni (0%)/Er	0.0618	4.2	2.175
Ni (1%)/Er	0.0797	4.1	1.646
Ni (2%)/Er	0.1486	4.2	0.904
Ni (3.5%)/Er	0.0477	4	2.683
Ni (5%)/Er	0.0557	4	2.298

Current intensity = 10 mA·cm⁻², electrolyte = 0.1 mol·L⁻¹ Na₂SO₄, and temperature = 25°C.