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The diffusional behaviour of H2 adsorbed in a novel mesoporous N-doped carbon material and on exfoliated graphite has been studied with quasi-elastic neutron scattering. While the activation energies for diffusion obtained for exfoliated graphite was in line with prior results, H2 in the mesoporous carbon showed an exceptionally low diffusion barrier and behaved qualitatively like liquid hydrogen. Complementary results from neutron and X-ray diffraction as well as from isothermal nitrogen sorption studies provide a full characterisation of this novel mesoporous carbon.

Polyaniline-silica composites made with mesoporous silica have been reported to improve the mechanical properties of the free polymer. However, there are not many studies about the effect of the chemical and physical properties of the inorganic material used as hosts over the final properties of polyaniline and the composites. Here, polyaniline-silica composites, exhibiting electrical conductivity, were synthesized using different types of SBA-16 mesoporous silica as hosts. The effects of the characteristics of the hosts in the polymerization kinetic, molecular weight and electrical conductivity of the final polymer were studied. The composites showed higher electrical conductivity in comparison with polyaniline synthesized under similar conditions of this work but in the absence of silica. The use of silica allowed to obtain composites with defined morphology, which did not occur in the absence of these hosts. From the results of this work, it can be concluded that SBA-16 mesoporous silica hosts have a bifunctional role in the formation of polyaniline-silica composites: the hosts behaved like nucleation sites, which favors polymerization of high molecular weight polyaniline and they catalyzed the polymerization reaction, especially when aluminum is present in the structure of the host.