Electrochemical Characterization of the Electrocrystalization of Bismuth on a Graphite Electrode

Bismuth electrocrystalization on a graphite electrode (GE) was studied by cyclic voltammetry and cronoamperometric techniques. Cyclic voltammetry shows that the electrocrystalization of is controlled by diffusion. Nucleation mechanisms depend on the imposed potential and time. Current transients were analyzed with the Sharifker-Hills model, the nucleation mechanism and growth of Bi on the GE is not a simple process, since at potentials between -210 and -240 mV, Bi electrocrystalization takes place in two different stages: at the first stage a 2D instantaneous mechanism can be recognized, followed in the second stage by a 3D progressive mechanism. For potentials lower than -260 mV only a 3D progressive nucleation mechanism can be recognize. These results imply that different characteristics for the Bi film can be obtained depending on the applied electrocrystalization potential, which can be considered for different applications.