Nanotubes made of boron nitride (BN) and carbon have attracted considerable attention within the literature due to their unique mechanical, electrical and thermal properties. In this work, BN and carbon nanotubes, exhibiting high purity (>99%) and similar surface areas (~200 m²/g), were systematically investigated for their thermal stability and oxidation behavior by combining thermal gravimetric analysis and differential scanning calorimetry methods at temperatures of up to ~1300 °C under a synthetic air flow environment. The BN nanotubes showed a good resistance to oxidation up to ~900 °C and fully transformed to boron oxide up to ~1100 °C, while the carbon nanotubes were stable up to ~450 °C and almost completely combusted up to ~800 °C. The different oxidation mechanisms are attributed to the different chemical nature of the two types of nanotubes.

New heterojunction materials (HJs) were synthesized in-situ by molecularly bonding the monomers of a triazine-based covalent organic framework (bulk COF) on the template of exfoliated carbon nitride (g-C₃N₄). The photocatalysts reduced carbon dioxide to carbon monoxide in aqueous dispersions under UV irradiation. The g-C₃N₄ showed production of 6.50 $\mathsf{\mu }$mol CO g⁻¹ h⁻¹ and the bulk COF of 2.77 $\mathsf{\mu }$mol CO g⁻¹ h⁻¹. The CO yield was evaluated in sustainability photoreduction cycles and their CO₂ uptake capacity and isosteric heat of adsorption were estimated. All the heterojunction photocatalysts obtained ameliorated CO production rates compared to the bulk COF. Finally, the influence of the Pt co-catalyst on the photocatalytic activities was determined without the addition of any sacrificial agent, and the COF:g-C₃N₄ heterojunction with the ratio of 1:10 was proven to be a photocatalytic system with an optimum and selective, CO yield of 7.56 $\mathsf{\mu }$mol g⁻¹ h⁻¹.

Hydrogen storage by cryoadsorption on porous materials has the advantages of low material cost, safety, fast kinetics, and high cyclic stability. The further development of this technology requires reliable data on the H₂ uptake of the adsorbents, however, even for activated carbons the values between different laboratories show sometimes large discrepancies. So far no reference material for hydrogen cryoadsorption is available. The metal‐organic framework ZIF‐8 is an ideal material possessing high thermal, chemical, and mechanical stability that reduces degradation during handling and activation. Here, we distributed ZIF‐8 pellets synthesized by extrusion to 9 laboratories equipped with 15 different experimental setups including gravimetric and volumetric analyzers. The gravimetric H₂ uptake of the pellets was measured at 77 K and up to 100 bar showing a high reproducibility between the different laboratories, with a small relative standard deviation of 3–4 % between pressures of 10–100 bar. The effect of operating variables like the amount of sample or analysis temperature was evaluated, remarking the calibration of devices and other correction procedures as the most significant deviation sources. Overall, the reproducible hydrogen cryoadsorption measurements indicate the robustness of the ZIF‐8 pellets, which we want to propose as a reference material.

Mixed matrix membranes (MMMs) containing UiO‐type metal‐organic frameworks (MOFs) have shown excellent potential for CO₂ separation processes due to their unique permeability and selectivity properties. However, while the performance of MOF‐based MMMs has been widely studied, the effect of structural defects and polymer‐filler compatibility are not yet fully understood. In this work, the CO₂ separation performance of Pebax MH1657‐based MMMs is systematically evaluated incorporating 5–20 wt% of Zr‐based MOF, including UiO‐66, UiO‐67, and two defect‐engineered UiO‐66 analogues, featuring extended linker (UiO‐66_A) or cluster (UiO‐66_F) vacancies. The structural, morphological, and thermal properties of the membranes are thoroughly characterized, with emphasis on correlating these features with gas transport performance. Single‐gas permeation experiments (CO₂, CH₄, H₂) reveal that incorporating UiO nanoparticles within the matrix consistently enhanced CO₂ permeability, reaching 145 Barrer for the 20 wt% UiO‐66_F MMM, a 216.4% increase over the neat membrane. CO₂/CH₄ and CO₂/H₂ selectivities also improve upon increasing MOF loadings, with UiO‐66_F achieving values of 25 and 18, respectively. This study provides insights for designing high‐performance MMMs for CO₂ separation applications, such as biogas upgrading and hydrogen purification.

Several crucial problems, such as rapid population growth and extended demands for food, water and fuels, could lead to a severe lack of clean water and an energy crisis in the coming decade. Therefore, low-cost and highly-efficient technologies related to filtration of alternative water supplies (e.g., purification of wastewater and water-rich liquids) and advanced energy storage (e.g., supercapacitors) could play a crucial role to overcome such challenges. A promising class of solid materials for these purposes is exfoliated graphene, and more specifically, its nanoporous forms that exhibit large specific surface areas and pore volumes. In the current work, two plasma-exfoliated graphene-based materials with distinctive morphological and porosity features, including non-porous and low-specific surface area platelets versus nanoporous and high-specific surface area flakes, were tested as filters for water purification purposes (i.e., decolourization and deacidification) and as electrodes for supercapacitors (i.e., ion electrosorption). The findings of this study suggest that a nanoporous and large specific surface area graphene-based material promotes the water purification behaviour by removing contaminants from water-based solutions as well as the energy storage performance by confining ions of aqueous electrolytes.