ELECTROSTATIC SELF-ASSEMBLED MULTILAYERS OF MESOPOROUS CARBON MICROPARTICLES

BALACH, J.; N. GUSTAVO COTELLA; ACEVEDO D.; BARBERO C

Bariloche

Workshop; US Argentina Workshop on Nanomaterials; 2009

cab

The carbonization of resorcinol–formaldehyde 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 m2/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 self-assembled 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.