Effect of surface structure of Au(1 0 0) electrode on phase transitions within adsorbed adlayer of coumarin in halide electrolytes in the presence of tetrabutylammonium cations

Highlights

• At Au(1 0 0)-hex in KBr and KCl solutions TBAc shift potential of phase transition.

• At Au(1 0 0)-hex in KI solution, TBAc do not induce the phase transition.

• At Au(1 0 0)-(1 × 1) in KBr new phase transitions within CUM adlayer were found.

• At nearly Au(1 0 0)-(1 × 1) in all halide solutions, TBAc induce the transition.

Abstract

Effect of surface structure of Au(1 0 0) electrode on the phase transitions within adsorbed adlayer of coumarin (CUM) in halide electrolytes in the presence of tetrabutylammonium cations (TBAc) was studied by means of cyclic voltammetry and differential capacity measurements. At the nearly unreconstructed surface of Au(1 0 0) electrode in chloride and bromide solutions, TBAc induced this transition, while at the reconstructed surface these cations caused a shift of it to more negative potentials. In KI as the supporting electrolyte, such phase transition was not detected at the reconstructed surface, but it was induced at the unreconstructed one. Additionally, new phase transitions in CUM adlayer have been found at the unreconstructed surface in bromide electrolyte, which are, however, completely inhibited by TBAc.