Polymeric Film Sensors based on PAH-PAZO Ionic Self-assembled Multi-nanolayers

Abstract

A sensor platform composed by interdigitated electrodes covered by a tailored nanofilm of 5 bilayers of PAH and PAZO polyelectrolytes was successfully built and tested in NaCl solution at relative low concentrations (10-10 M). The effect of temperature on the electrical measurements was addressed and indicated its importance for to sake accuracy reduction in about one order of magnitude. The film morphology was studied by using ellipsometry and atomic force microscopy techniques. The first inferred precise and consistent values for the film thickness about 50 nm. With respect to the second, relative low values of the surface roughness of about few nanometers were measured and also micrometer diameter agglomerates and channels with a bilayer size depth were identified.