With TEMPO oxidation, it was possible to incorporate iron nanostructures into a cellulose nanofiber matrix. FTIR spectra showed the functional groups present in the films. The combination of both iron and CNF confers to the films good electrochemical activity; the electrochemical characterization (CV) showed that they present stability in the reduction process at a potential of 0–1 V, with the materials with 5% and 10% being the most active. The Pb reduction process shows that the 5% film is the material with the highest oxidizing capacity.