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A biomimetic sensor containing the oxo‐bridged dinuclear manganese‐phenanthroline complex incorporated into a cation‐exchange polymeric film deposited onto glassy carbon electrode for detection of sulfite was studied. Cyclic voltammetry at the modified electrode in universal buffer showed a two electron oxidation/reduction of the couple MnIV(μ‐O)2MnIV/MnIII(μ‐O)2MnIII. The sensor exhibited electrocatalytic property toward sulfite oxidation with a decrease of the overpotential of 450 mV compared with the glassy carbon electrode. A plot of the anodic current versus the sulfite concentration for potential fixed (+0.15 V vs. SCE) at the sensor was linear in the 4.99×10−7 to 2.49×10−6 mol L−1 concentration range and the concentration limit was 1.33×10−7 mol L−1. The mediated mechanism was derived by MichaelisMenten kinetics. The calculated kinetics values were MichaelisMenten rate constant=${K{{{\rm app}\hfill \atop {\rm M}\hfill}}}$=1.33 µmol L−1, catalytic rate constant=6.06×10−3 s−1 and heterogeneous electro‐chemical rate constant=3.61×10−5 cm s−1.

The supramolecular building blocks from nickel(II) bisalphen-type complex was reported. The conjugations through the bridge provide a flexibility of monomer in the electropolymerization stage. Thus, different structures can be obtained with the variation of electrochemical parameters used in the electropolymerization. The structural characterization and the electrochemical behavior in aqueous solution was also evaluated, which demonstrating that the electropolymerization mechanism was similar to observed to the classical salen polymers, but the molecular organization onto conductor substrate is different. The supramolecular structure of polymeric film allows observe the Ni I /Ni II and Ni II /Ni III redox couple by differential pulse voltammetry. Thus, the comproportionation constant and Gibbs energy were calculated by Ni I /Ni II redox couple. These characteristics make these polymer versatile materials the field of supramolecular chemistry and material science, in particular to application as sensor, in electrocatalysts and energy storage.

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