Extraordinary properties of graphenic materials no longer need to be demonstrated. Nitrogen doping has been known to broaden the graphene application fields, especially for catalysis purposes. The present work reports a solvothermal-based process for the synthesis of a nitrogendoped graphenic foam with up to 2.6 at.% nitrogen, exhibiting the inherent properties of graphenic materials with high textural properties and surface areas as high as 2243 m².g-1. This study aims to give a better understanding of the influence of the pyrolysis treatment on the properties of the produced material for optimization of the synthesis in view to fuel cell applications. Several cross-linked techniques such as transmission electron microscopy, thermogravimetric analysis, Raman spectroscopy, nitrogen physisorption at 77 K and X-ray photoelectron spectroscopy have been employed to give a complete, precise characterization of the elaborated N-doped graphenic foams, leading to optimized conditions for the pyrolysis step. Pyrolysis at 850 °C has been found to allow the best compromise in terms of purity, homogeneity and crystallinity, with high fractions of pyrrolic, pyridinic and graphitic Nsubstitution that are known to greatly enhance the material catalytic properties. An oxidative degradation process was also evidenced for temperatures above 875 °C, leading to far lower graphene amounts.

Despite the apparent simplicity of palladium hydride systems, interactions between hydrogen and palladium are multifaceted. Electrochemical hydrogen stripping allows measuring the stoichiometric coefficient of hydrogen atoms inside PdHx structures, whose properties greatly depend on x. In this paper, the insertion of H into Pd nanoparticles has been studied in a three‐electrode setup (RDE) and a proton pump cell. An original way of modelling the hydrogen desorption curve is proposed, helping in the separation of hydrogen absorption from other contributions. The loading voltage exhibits the highest impact on the H absorption into Pd, reaching Habs/Pd up to 0.47±0.02 in the RDE setup, at −0.2 VRHE. Conversely, the loading duration presents only little influence in the very first seconds. Finally, maximal Habs/Pd ratios are measured around 30–40 °C, likely due to an optimal balance between the H adsorption rate, and the H diffusion rate into Pd.

The decoration of carbon nanotubes (CNTs) by metal nanoparticles (NPs) combines the advantages of a high specific surface material with catalytic properties of metal nanocrystals. Little work has been devoted to the decoration of CNTs with copper NPs, and no evidence of copper atomic decoration of CNTs has shown up until now. Herein, we demonstrate that the strong acidic oxidation of double-walled CNTs (dwCNTs) is very efficient for the decoration of the carbon surface by copper NPs and atoms. This treatment severely degraded the CNT walls and generated a large amount of disordered sp 3 carbon. This amorphous carbon film bears many chemically active functions like carboxyl and hydroxyl ones. In such conditions, the CNT walls behave as very efficient ligands for the stabilization of copper obtained by the thermolysis of the mesityl precursor in organic solution under mild dihydrogen pressure. In addition to copper NPs, we evidenced the presence of a regular coverage with copper atoms over the dwCNTs. This nanocomposite catalyzes the quantitative synthesis of propargylamines via one A 3 -type coupling reaction. Five consecutive catalytic cycles with 100% yield could be performed with no loss of activity, and the combination of Cu supported on dwCNTs allows a facile recycling of the catalytic material.