This paper describes the exohedral N-decoration of multi-walled carbon nanotubes (MWCNTs) with NH-aziridine groups via [2+1] cycloaddition of a tert-butyl-oxycarbonyl nitrene followed by controlled thermal decomposition of the cyclization product. The chemical grafting with Ncontaining groups deeply modifies the properties of the starting MWCNTs, generating new surface microenvironments with specific base (Brønsted) and electronic properties. Both these features translate into a highly versatile single-phase heterogeneous catalyst (MW@N Az ) with remarkable chemical and electrochemical performance. Its surface base character promotes the Knoevenagel condensation with superior activity to that of related N-doped and N-decorated carbon nanomaterials of the state-of-the-art; the N-induced electronic surface redistribution drives the generation of high energy surface "C" sites suitable for O2 activation and its subsequent electrochemical reduction (ORR).

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Covalent triazine-based frameworks (CTFs) were synthesized in large scale from various monomers. The materials were post-synthetically modified with acid functionalities via gas-phase sulfonation. Acid capacities of up to 0.83 mmol g À1 at sulfonation degrees of up to 10.7 mol% were achieved. SulfonatedCTFs exhibit high specific surface area and porosity as well as excellent thermal stability under aerobic conditions (>300 C). Successful functionalization was verified investigating catalytic activity in the acidcatalyzed hydrolysis of cellobiose to glucose at 150 C in H 2 O. Catalytic activity is mostly affected by porosity, indicating that mesoporosity is beneficial for hydrolysis of cellobiose. Like other sulfonated materials, S-CTFs show low stability under hydrothermal reaction conditions. Recycling of the catalyst is challenging and significant amounts of sulfur leached out of the materials. Nevertheless, gas-phase sulfonation opens a path to tailored solid acids for application in various reactions. S-CTFs form the basis for multi-functional catalysts, containing basic coordination sites for metal catalysts, tunable structural parameters and surface acidity within one sole system.

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This work presents the application of nitride membranes produced with Si-MEMS-technology as a platform to build up new membrane-electrode assemblies (MEA) for alkaline fuel cells. Active alkaline fuel cell MEAs were combined by integrating hydroxide permeable electrolyte into micro-channels of 1 μm diameter in 5 to 10 μm thick MEMS-based membranes. A platinum catalyst was sprayed onto the surface and an electric conductive layer was applied on top. Taking advance of the small form factor these fuel cells can be applied in small devices with low energy demand.