Hyperbranched polyester-polyol assemblies on carbon electrodes: Preparation, Characterization and Application to Electrocatalysis

ELIANA D. FARÍAS; VALERIA N. SUELDO OCCELLO; MARIO C. G. PASSEGGI (H); VERONICA BRUNETTI

Congreso; 13th ECHEMs:electrochemistry for symmetry breaking in molecules, materials and processes.; 2019

Highly branched dendritic polymers have gained more consideration due to their exceptional properties, which differ significantly from their linear counter parts, e.g. multiple terminal functional groups, specific rheological properties based on their globular structure, and well-defined internal cavities available to encapsulate guest molecules [1]. In this work, we analyze the spontaneous adsorption of a family of hyperbranched polyester-polyols polymers on carbon electrodes with the aim of generating nanostructured surfaces with the ability to capture or retain silver cations inside the film. Along this work, adsorption kinetics, interfacial properties, and thermal transitions of the polymers under confinement, are revealed by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and atomic force microscopy (AFM). The dependence of the nanometer-sized layers against temperature revealed a thermal transition close to the Glass Transition Temperature of the polymer in bulk, but this phase transition should be explained in terms of layer reorganization, from a porous multilayer to a more compact film due to the temperature effect on the intermolecular hydrogen-bonding and the adsorbate-substrate interactions, instead of a glass transition [2]. This feature is of particular relevance for further applications of hyperbranched polymers thin films in nanodevices. Moreover, these platforms have showed an excellent capability to act as electrocatalytical platform for peroxide hydrogen after silver ions encapsulation, useful for the development of non-enzymatic electrochemical sensors.