Electrochemical costripping models and mutual interferences of mutli-transition metal systems on the surface of boron-doped diamond

Electrochemical behaviors of electrodeposition stripping of some transition metals, such as Ag, Cu, Pb, Sn, and Cd were investigated on boron-doped diamond (BDD) film with differential pulse anodic stripping voltammetry (DPASV). The results show that the metal costripping process on the surface of BDD is influenced by deposition potential of transition metals, potential of hydrogen evolution reaction, mutual interferences between two transition metals, and so on. Electrochemical costripping models and mutual interferences of binary transition metals are proposed. (i) When the hydrogen evolution potential is higher or lower than the deposition potential of two transition metals, the metals do not form alloys and compound the cathode ions in the solution, and the costripping process conforms to metal 1 stripping-metal 2 stripping. (ii) When the hydrogen evolution potential is between the deposition potential of two transition metals, the metals do not form alloys and compound the cathode ions in the solution, and the costripping process conforms to metal 1 stripping-hydrogen evolution-metal 2 stripping. (iii) When two transition metals form alloys, the costripping process conforms to metal 1 stripping-alloy striping-metal 2 stripping. (iv) When the hydrogen evolution potential is between deposition potential of two transition metals, and transition metal 2 is complexed with one kind of cathode ion in the solution, the costripping process conforms to metal 1 stripping-hydrogen evolution-metal 2 complex formation-metal 2 stripping. Moreover, the electrochemical-costripping model of two transition metals in a solution with three or more transition metals, is similar to that in the binary system. It is also found that various metals electrodeposited on BDD film in the form of single metal or alloy can be completely stripped away by the constant-potential electrolysis technique at 2.8 V for 10 s.