Influence of microporosity of activated carbons as a support of polyoxometalates

H-3[PMo12O40] (PMO) was supported on four activated carbons (AC) in order to analyze the influence that the porous texture of AC exercises in the adsorption of PMo, trying to study where they are adsorbed and how their adsorption modifies the porous texture of AC. The amount of PMo adsorbed on AC follows a clear correlation with the porous texture, microporosity being the best evidence for this. Such a correlation indicates that PMo is only adsorbed in supermicroporosity as a consequence of the size of PMo, which limits the entrance on the smallest micropores, about 0.8 nm. XRD results indicate that the PMo is adsorbed on the micropore wall, that it is highly dispersed and that it does not develop any crystalline phase. (c) 2008 Elsevier Inc. All rights reserved.