Redox transformations in electroactive polymer films derived from complexes of nickel with SalEn-type ligands: computational, EQCM, and spectroelectrochemical study

Nickel- N,N’ – bis (salicylidene)-1,3-propanediamine (Ni- Salpn ) film-modified electrodes. Influence of electrodeposition conditions and of electrode material on electrochemical behaviour in aqueous solution

“…It was found that the values of E m are proportional to the ratio [ionic charge]/[ionic radius] of the anion present in solution for NO 3 − , ClO 4 − and SO 4 2− , Fig. 10, confirming the dependence on the mobility of the counterions of the supporting electrolyte in charge transport and in maintaining electroneutrality during potential cycling [1,2,46]. The higher value of E m obtained for Cl − ions compared with NO 3 − , which has a similar size [48], may indicate that Cl − has a different interaction within the Ni-Salpn film structure.…”

“…A decrease of frequency during the positive sweep (above +0.5 V vs. Ag/AgCl), can be attributed to insertion of anions into the film structure, and an increase during the negative sweep (below +0.75 V vs. Ag/AgCl) to anion extraction, where the incorporation of anions is dominant, a mechanism essential for maintaining electroactivity [45,46].…”

Understanding the Charge Storage Mechanism and Electrochemical Performance on the Poly[Ni(salen)]-modified Electrode Electropolymerized with Different Sweep Rate

“…[1][2][3][4] The salen type transition metal conducting polymer could be polymerized to the anode and form electrochemical active films in solvents with weak donor numbers (acetonitrile and solvents with lower DN values) which prompted their use in heterogeneous electrocatalysis. [5][6][7] In nonaqueous electrolyte system, the electroactive films could not only change reversibly at a higher voltage between neutral and oxidation state, 8 but also can change reversibly at a lower voltage between neutral and reduction state, 9,10 in order to storage and release charge continuously. In addition, this kind of polymeric transition mental complexes is widely believed to possess both redox conductivity and electron conductivity, 8,9 which leads to dramatic changes in high rate charge transition.…”

Interaction of amines with electrodes modified by polymeric complexes of Ni with salen-type ligands

“…Previous studies have largely been focused on metal complexes with unsubstituted salen ligands. However, it is well known that oxidation of salen complexes is ligand-based, at least at the first oxidation step [2,[11][12][13]. This provides for flexible fine-tuning of electronic properties of salen-based materials via introducing various functionalities in the imine bridge and aldehyde moiety of the ligand.…”

“…Square-planar complexes of transition metals with N,N'-ethylenebis(salicylimine) (salen) type ligands ([M(Schiff)]) are known as effective electron transfer catalysts and redox mediators due to possibility of exogeneous ligands axial coordination to the metal center of the oxidized form of the salen complex [1][2][3][4]. This makes chemically modified electrodes based on [M(Schiff)] polymers and thin films promising systems for amperometric and voltammetric detection of various compounds, such as nitric oxide [5], pyridine [6], pyridoxine [7], cysteine [8,9], and dipyrone [10].…”