Electrochemical quartz crystal microbalance study on the two-electrode-system cyclic voltammetric behavior of Prussian blue films

Abstract

A two-channel electrochemical quartz crystal microbalance (EQCM) was used to investigate the cyclic voltammetric behavior of two Prussian blue (PB) film-modified Au electrodes in a two-electrode configuration in aqueous solution. The redox peaks observed in the two-electrode cyclic voltammogram (CV) are assigned to the intrinsic redox transitions among the Everitt's salt, PB, and Prussian yellow for the film itself, the redox process of the Au substrate and the redox process of small-quantity ferri-/ferrocyanide impurities entrapped in the PB film, as also supported by ultraviolet-visible (UV-Vis) spectroelectrochemical data. The profile of the two-electrode solid-state CV for the PB powder sandwiched between two gold-coated indium-tin oxide (ITO) electrodes is similar to that for two PB-modified Au electrodes in aqueous solution, implying similar origins for the corresponding redox peaks. The two-channel EQCM method is expected to become a highly effective technique for the studies of the two-electrode electrochemical behaviors of many other species/materials. Prussian blue (PB), two-electrode liquid-/solid-state cyclic voltammetric behavior, two-channel electrochemical quartz crystal microbalance, UV-Vis spectroelectrochemistry

Three-dimensional activated graphene network–sulfonate-terminated polymer nanocomposite as a new electrode material for the sensitive determination of dopamine and heavy metal ions

“…Cobalt species can serve as a catalyst for carbon graphitization during the carbonization process, so it is reasonable that highly graphitized 3DAGNs were obtained. 43,44 In the experiment, the 3DAGN-STP nanocomposite was cast-coated on a PQC, and the frequency shift (Δf 0 ) and resistance change (ΔR 1 ) were monitored in stirred PBS ( pH 7.0). S2b and c (see ESI †) show the nitrogen adsorption-desorption isotherms and pore size distribution of the 3DAGNs.…”

“…In the FT-IR spectrum of the 3DAGNs, the band at 1585 cm −1 is assigned to the stretching vibration of the benzenoid ring, and the band at 1100 cm −1 is the stretching The adhesive force of the 3DAGN-STP nanocomposite on the electrode area was examined with the QCM technique, which is capable of the in situ detection of nanogram-scale mass changes on the electrode surface. 43,44 In the experiment, the 3DAGN-STP nanocomposite was cast-coated on a PQC, and the frequency shift (Δf 0 ) and resistance change (ΔR 1 ) were monitored in stirred PBS ( pH 7.0). As shown in Fig.…”

“…The value of |Δf 0 /ΔR 1 | is higher than 10 Hz/Ω here indicating that the f 0 and R 1 responses originate from a net mass effect. 43 The pK a value of DA is 8.87, so DA is positively-charged in PBS ( pH 7.0). Thus it is reasonable that DA can be adsorbed by the 3DAGN-STP via electrostatic interactions.…”