INVESTIGADORES
BALACH juan Manuel
congresos y reuniones científicas
Título:
Electrostatic self-assembled multilayers of mesoporous carbon microparticles
Autor/es:
JUAN M. BALACH; N. GUSTAVO COTELLA; DIEGO F. ACEVEDO; CÉSAR BARBERO
Lugar:
San Carlos de Bariloche, Argentina
Reunión:
Workshop; US_Argentina Workshop on Nanomaterials; 2009
Resumen:
The carbonization of resorcinolformaldehyde resins, obtained by condensation
of resorcinol with formaldehyde in aqueous media with surfactant micelles as
nanotemplate,[1] produce mesoporous carbons. The materials have large
specific surface areas (> 500 m
2
/g) making them useful in applications where a
large electrochemically accessible area is required. However, monolithic porous
carbons show slow responses due to the long pathway of the pores. A way to
avoid that is using materials built by particles electrically connected but
permeable to the electrolyte. The formation of electrostatic self-assembled
multilayers (ESAMU) by a layer-by-layer (LbL) procedure was introduced by
Decher in 1991.[2] The popularity of the method is due to the ability to build
functional layers ordered in the space. Usually is applied to macromolecules or
nanoparticles. Here, we describe the assembly of ESAMUs with mesoporous
carbon microparticles. Mesoporous carbon microparticles were made by milling
and sieving porous carbon or emulsion polymerization. The particles are selfassembled with a polylectrolyte (PDAMAC). The electrochemical properties of
the particles were probed using a redox probe. The results suggest that a
hierarchical control of the diffusion of redox probes exists in the system. By
adsorption of redox molecules (e.g. quinones) onto the inner carbon surface it is
possible to construct electrodes with pseudocapacitive behaviour.