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N-doped graphene hydrogels were prepared by crosslinking graphene oxide with ethylenediamine. These materials presented 10 at. % nitrogen, as determined by X-ray photoelectron spectroscopy. N-doped graphene was entangled within mesoporous matrices by diffusion of resorcinol-formaldehyde solutions throughout the hydrogels. According to nitrogen desorption isotherms, N-doping graphene slightly reduces the pore size and volume toward values closer to the graphene-free resins. The underlying graphene framework was observed within the amorphous porous carbon by transmission microscopy. These porous materials were impregnated with LiBH4 at 30, 50 and 70 vol %. Differential scanning calorimetry of the nanoconfined hydrides illustrates how N-doped matrix promotes a decrease in LiBH4 decomposition temperature, and this effect was quantified by volumetric studies. Powder diffraction revealed a peak at 12.6° attributed to the interaction of LiBH4 with the N-doped matrix. Owing to Yates analysis, N-doping lowers hydrogen release temperature by 10 °C, while at 325 °C the quantity released is increased by 1 wt %. This effect is more important than the diminution of pore size from 10 to 5 nm and compensates the presence of graphene. The benefit from N-doping is more remarkable for lower size of pores and higher LiBH4 filling, as illustrated by the proposed model.

LaNiO perovskite is a promising electrocatalyst for the oxygen reduction reaction (ORR). In this work we study the effects of several key structural and morphological features on the performance of LaNiO perovskites for the ORR. We have prepared a series of LaNiO oxides via soft chemistry and calcined the final materials at different temperatures from 500 to 1000 °C. With the aim of obtaining morphological and structural information relevant to their performance the prepared oxides have been thoroughly characterized by BET, Power Neutron Diffraction (PND), XRD, HRTEM, STEM-HAADF and XPS. We have analysed the effect of extrinsic (surface area and particle size) and intrinsic factors (formation of oxygen vacancies, Ni oxidation states and occupancy of the e levels) on the current densities and specific activity, respectively, of several samples of LaNiO. The catalysts with higher catalytic activity are those in which the perovskite structure is properly formed, but display high surface areas., María Retuerto acknowledges the Juan de la Cierva program of the Spanish Ministry of Economy and Competitiveness for a grant (FPDI-2013-17582). Economic support from projects ENE2013-42322-R from the Spanish Ministry of Economy and Competitiveness, and project 201480E122 from the CSIC are also acknowledged. Project S2013/MAE-2882 is also acknowledged. J. A. Alonso and M. Teresa Fernández-Diaz thank the financial support of the Spanish Ministry of Science and Innovation to the project MAT2013-41099-R. Amaru González acknowledges the SECAT for a grant.