Nucleacion y Crecimiento en la Sintesis de Nanocompuetsos de Ag/polianilina

MARIA DEL CARMEN AGUIRRE.

Rio IV

Encuentro; NANO20/22 .XXI Encuentro de Superficies y Materiales Nanoestructurados; 2022

AbstractNucleation and growth mechanisms in the synthesis of polyaniline nanowires (PANI NWs) and of silver nanoparticles (AgNPs) which are assembly to PANI NWs, are proposed. Aniline polymerization proceeds over a graphite electrode, at potentials that go from 0.9 V to 1.15 V (vs Ag/AgCl), using: 0.25, 0.15, or 0.05 M of aniline in HNO3 solution. In the polyaniline nucleation and growth is postulated a diffusional 3D model that involves the dendrites formation and the unidirectional growing step. At lowest aniline concentration, the transients displayed the typical peaked shape, characteristic of a 3D nucleation and diffusion-controlled growth. Silver nanoparticles are synthesized on the polyaniline/graphite substrate. Current-time transients at –0.1V and –0.2V (vs Ag/AgCl), displayed a decreasing in the current which is fit to Cotrell modified diffusion-limited aggregation model. Nanowires and nanoparticles morphology observed by SEM corroborated the proposed mechanisms.Keywords: PANI NWs, growth and nucleation mechanism, AgNPs, nanocomposite.