On the Hybrid Glassy Carbon Electrode/OligoThiophene/Ag(NP) Interface

GC/OligoThiophene/Ag(NP) hybrid interfaces
are synthesized and characterized: GC is the glassy carbon
surface; OligoThiophene stands for both an ultrathin
bithiophene grafted film and a 4-Br-Bithiophene grafted
polymer; Ag(NP) stands for silver nanoparticles. The hybrid
interface preparation involves different steps: first, the
electrode surface is functionalized through a combination of
electrochemically assisted grafting (under reduction regime)
and polymerization (under oxidation regime); then, silver nanoparticles are chemisorbed by dipping. In particular, an ultrathin
film of grafted bithiophene can be obtained by applying one cyclic voltammetry reduction cycle (GC/BT surface), while
subsequent cyclic voltammetry cycling under oxidation regime yields an immobilized 4Br-Bithiophene polymer (GC/4BrBT
surface). AFM and TEM images were recorded to investigate the morphology and chemical composition of the Ag(NP). FeII/
FeIII cyclic voltammetry, Zn underpotential deposition (UPD), XPS, LA-ICP-MS, and Raman techniques were exploited to
characterize both the GC/OligoThiophene and GC/OligoThiophene/Ag(NP) interfaces. Theoretical calculation, at the B3LYP/
6-311G** level of the theory, enabled rationalization of the electroreduction mechanism and the Raman results.