Micromechanical modeling-based self-consistent scheme of polymer-layered silicate nanocomposites

Although few investigations recently proposed to describe the overall elastic response of polymer-clay nanocomposites using micromechanical-based models, the applicability of such models for nanocomposites is far from being fully established. In this communication, we present a micromechanical approach for the prediction of the overall moduli of polymer-clay nanocomposites using a self-consistent scheme based on the double-inclusion model. The efficiency of the proposed model to predict the experimental elastic response of various polymer-clay nanocomposites is pointed out

Platinum particles deposited on synthetic boron-doped diamond surfaces: application to methanol oxidation

Two methods have been used for the deposition of Pt particles on synthetic boron-doped diamond (BDD) surfaces: chemical deposition and electrodeposition under potentiostatic conditions. However, electrodeposition leads much higher platinum dispersion than chemical deposition. The mechanism of nucleation and growing of the electrodeposited platinum was investigated by means of chronoamperometric studies in acid medium. The electrodeposition on diamond surfaces shows a mechanism of progressive nucleation as deduced from the chronoamperometric studies in acid medium. The stability of the deposited platinum is very low and the platinum particle are dissolved/detached by cycling. The modified BDD electrodes by deposition of platinum have been tested for the oxidation of methanol, showing that multi-step deposition results in higher values of surface and mass activities for methanol oxidation than one-step deposition process.Ministerio de Ciencia y Tecnología (MAT2001-1007