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Polypyrrole (PPy) has been prepared by oxidative polymerization of pyrrole and used as a raw material for the preparation of N-doped activated carbons. Thus, PPy has been pyrolyzed at 900 °C and then activated with steam under different activation conditions (time and temperature). This has allowed for the preparation of activated carbons with different porosity development and nitrogen content, as well as distinctive distribution of nitrogen species. It has been observed that the presence of nitrogen functionalities favors water adsorption at low relative pressures but, at relative pressures higher than 0.5 it is determined by the porosity development. Financial support from Ministerio de Ciencia e Innovación (Spain, Project PID2019-108453GB-C21) is gratefully acknowledged. Open access funding enabled and organized by Projekt DEAL.

MXenes are a new family of 2D carbides or nitrides that have attracted attention due to their layered structure, tunable surface groups and high electrical conductivity. Here, we report for the first time that Ti 2 CT x MXene catalyses the selective oxidative dehydrogenation of n -butane to butenes and 1,3-butadiene. This catalyst showed higher intrinsic activity compared to commercial TiC and TiO 2 samples in terms of C 4 olefin formation rate. We propose that the stabilisation of structural vacancies and the change in composition (from a carbide to a mixed phase oxide) in the MXene causes its higher catalytic activity. These vacancies can lead to a higher concentration of unpaired electrons in the MXene-derived material, enhancing its nucleophilic properties and favouring the production of olefins. We thank the Netherlands Organization for Scientific Research (NWO) for the grant “Developing novel catalytic materials for converting CO2, methane and ethane to high-value chemicals in a hybrid plasma-catalytic reactor” (China.15.119). EVRF thanks the “Ministerio de Ciencia e innovación” grant (PID2020-116998RB-I00).

We report a facile and general approach for preparing ultrafine ruthenium nanocatalysts by using a plasma-assisted synthesis at

MAX (Mn+1AXn) phases are layered carbides or nitrides with a high thermal and mechanical bulk stability. Recently, it was shown that their surface structure can be modified to form a thin non‐stoichiometric oxide layer, which can catalyze the oxidative dehydrogenation of butane. Here, the use of a Ti2AlC MAX phase as a support for cobalt oxide was explored for the dry reforming of butane with CO2, comparing this new catalyst to more traditional materials. The catalyst was active and selective to synthesis gas. Although the surface structure changed during the reaction, the activity remained stable. Under the same conditions, a titania‐supported cobalt oxide catalyst gave low activity and stability due to the agglomeration of cobalt oxide particles. The Co3O4/Al2O3 catalyst was active, but the acidic surface led to a faster deactivation. The less acidic surface of the Ti2AlC was better at inhibiting coke formation. Thanks to their thermal stability and acid‐base properties, MAX phases are promising supports for CO2 conversion reactions., Take it to the MAX: The reaction of carbon dioxide with butane to give syn‐gas is a valid method for converting CO2 into something useful and is catalyzed efficiently by cobalt oxide supported on a MAX phase.

Platinum nanoparticles supported on titania efficiently catalyzed the diboration of alkynes and alkenes under solvent- and ligand-free conditions in air. The cis-1,2-diborylalkenes and 1,2-diborylalkanes were obtained in moderate to excellent yields following, in most cases, a simple filtration workup protocol. The versatility of the cis-1,2-diboronvinyl compounds was demonstrated in a series of organic transformations, including the Suzuki–Miyaura cross coupling and the boron–halogen exchange. This work was generously supported by the Spanish Ministerio de Economía y Competitividad (MINECO; CTQ2007-65218 and CTQ2011-24151), the Generalitat Valenciana (GV; PROMETEO/2009/002 and PROMETEO/2009/039), and FEDER.

Pt/TiO2-catalyzed diborations of terminal and internal alkynes (I, IV and VI) as well as cyclic alkenes (XII) run in a stereoselective manner (cis-diboration).

Global warming issues and the medium-term depletion of fossil fuel reserves are stimulating researchers around the world to find alternative sources of energy and organic carbon. Biomass is considered by experts the only sustainable source of energy and organic carbon for our industrial society, and it has the potential to displace petroleum in the production of chemicals and liquid transportation fuels. However, the transition from a petroleum-based economy to one based on biomass requires new strategies since the petrochemical technologies, well-developed over the last century, are not valid to process the biomass-derived compounds. Unlike petroleum feedstocks, biomass derived platform molecules possess a high oxygen content that gives them low volatility, high solubility in water, high reactivity and low thermal stability, properties that favour the processing of these resources by catalytic aqueous-phase technologies at moderate temperatures. This tutorial review is aimed at providing a general overview of processes, technologies and challenges that lie ahead for a range of different aqueous-phase transformations of some of the key biomass-derived platform molecules into liquid fuels for the transportation sector and related high added value chemicals.

It allows efficient, regio- and stereoselective formation of a wide range of vinyl silanes.

Two copper ion-exchanged zeolites, Cu/NaY and Cu/NaZSM-5 have been studied by several techniques (TPR, TPD of NO, IR spectroscopy of adsorbed NO and XPS) and their catalytic activity for NO decomposition have been determined under dynamic conditions. The results obtained here show that copper' is stabilized as Cu+ in Cu/NaZSM-5 after calcination in air at 673 K, while in Cu/NaY the initial Cu+ ions are easier oxidized to Cu2+, this leading to a completely different catalytic behaviour in the reaction of NO decomposition. So, whereas the Cu/NaZSM-5 exhibits a high NO conversion at the reaction temperatures (573 and 873 K), the parent Cu/NaY zeolite becomes deactivated in the first stages of reaction.

Pt/activated carbon catalysts were prepared by using [Pt(NH3)4]Cl2 as the metal precursor, and characterized by a number of techniques. The selectivity of these catalysts towards crotyl alcohol in the gas-phase hydrogenation of crotonaldehyde was considerably increased when the activated carbon support was slightly oxidized before the metal incorporation.

SiC–MoSi2 ceramic composite materials with controlled molybdenum content can be prepared by reaction of silicon with previously formed molybdenum carbide.