This work evaluates the electrocatalytic oxidation of hydrazine (HDZ) by silver (AgHCF) and copper (CuHCF) hexacyanoferrates-modified glassy carbon electrodes kinetically and analytically through experimental electrochemistry and theoretical approaches
The materials were prepared by a two-step cyclic voltammetry (CV) routes
The AgHCF and CuHCF-modified electrodes showed quasi-reversible characteristics driven by K+ diffusion and adsorption processes, respectively.
The analyte exhibited irreversible electron transfer controlled by semi-infinite diffusion process for both Prussian blue analogs.
Theoretical approaches showed that CuHCF material required lower energy (ΔEgap = 0.0397 eV) to promote an electron to the lowest unoccupied molecular orbital due to its cubic structural arrangement,
justifying the better electrocatalytic results comparing to the hexagonal structure of the AgHCF material (ΔEgap = 0.0840 eV).
Atomic details of the orbitals involved in HOMO→LUMO energy gap were investigated using density functional theory (DFT) calculations
This work aims at the experimental and theoretical studies of HDZ electrocatalytic response of two electrochemically prepared PBA: AgHCF and CuHCF and promotes a discussion about what features are involved in this specific application.
A peak current increasing starting at −0.3 V indicates the deposition of the metal particles through the reaction Cu2+(aq) + 2e− → Cu0(s)
This phenomenon represents the potential where the nucleation of metallic species happens, called crossover potential
The subsequent cycles also demonstrate the same property, which suggests that new nucleation sites are being created through the whole deposition.
the CuHCF solid is a better oxidation agent than AgHCF.
the energy required to promote electron between HOMO→LUMO orbitals is lower in CuHCF (0.0397 eV) than AgHCF (0.0840 eV)