We report on the N-decoration of multiwalled carbon nanotubes (MWCNTs) via chemical functionalization under mild reaction conditions. The introduction of tailored pyridinic functionalities as N-containing edge-type group mimics generates effective catalysts for the oxygen reduction reaction (ORR) in an alkaline environment. The adopted methodology lists a number of remarkable technical advantages, among which is an easy tuning of the electronic properties of N-containing groups. The latter aspect further increases the level of complexity for the rationalization of the role of the N-functionalities on the ultimate electrochemical performance of the as-prepared metal-free catalysts. Electrochemical outcomes crossed with the computed electronic charge density distributions on each scrutinized pyridine group have evidenced the central role played by the N-chemical environment on the final catalyst performance. Notably, small variations of the atomic charges on the N-proximal carbon atoms of the chemically grafted heterocycles change the overpotential values at which the oxygen reduction reaction starts. The protocol described hereafter offers an excellent basis for the development of more active metal-free electrocatalysts for the ORR. Finally, the as-prepared catalytically active materials represent a unique model for the in-depth understanding of the underlying ORR mechanism.

In this paper, we review different plasma processes developed in our laboratory to obtain nanostructured superhydrophobic polymer surfaces. All methods consist of a single step and lead to functional materials which combine a fluorinated chemistry with unique surface morphologies. The transition from sticky to slippery superhydrophobicity, crucial for several applications ranging from microfluidics to outdoor self‐cleaning surfaces, is found by properly tuning process parameters. Methods are compared in terms of process time‐scale and compatibility to different substrates. magnified image

A novel lead-free 2D perovskite, namely PEA₂SnBr₄, shows impressive water-resistance by retaining its original crystal structure and optical properties when placed in contact with water. Such key properties have been advantageously used for the fabrication of a novel co-catalytic system by coupling PEA₂SnBr₄ with graphitic carbon nitride. PEA₂SnBr₄/g-C₃N₄ composites at different metal halide perovskite loadings (5 and 15 wt%) have been prepared and tested in hydrogen photogeneration in an aqueous environment and organic dye degradation (methylene blue). The results show an impressive enhancement of H₂ production of the composite with respect to the two separate components with hydrogen evolution rates up to 1600 μmol g⁻¹ h⁻¹ and analogous improvements in the efficiency of methylene blue degradation. The present results, providing a novel water-resistant perovskite and co-catalytic system, pave the way towards the safe, efficient and real use of metal halide perovskites in catalysis.