Nucleation and Growth of Gold Nanoparticles on a Poly5Aphen-Modified Glassy Carbon Electrode from a Deep Eutectic Solvent

In this work, the mechanism of nucleation and growth of gold was studied on the surface of a glassy carbon electrode (GCE) modified with poly-5-Amino-1-10 phenanthroline (Poly5Aphen), from Au (III) ions, dissolved in a deep eutectic solvent (DES). For which, electrochemical techniques such as cyclic voltammetry (VC) and chronoamperometry (CA) were used. The analysis of the results of the potentiostatic electrochemical tests showed that the Au nucleation and growth mechanism on the GCE/Poly5Aphen electrode fits a theoretical model of 3D nucleation limited by diffusion and by the reduction of residual water present in the electrode (1). In addition, the potentiostatic current density transients recorded during gold electrodeposition on the modified electrode (GCE/Poly5Aphen), when presented in their dimensionless form I2/ I2 m vs t /tm and compared with the theoretical models described by Scharifker and Hills (2), the experimental data did not fit the progressive or instantaneous nucleation models, presenting particularly large deviations for >1.4.