Designing next-generation fuel cell and filtration devices requires the development of nanoporous materials that allow rapid and reversible uptake and directed transport of water molecules. Here, we combine neutron spectroscopy and first-principles calculations to demonstrate rapid transport of molecular H2O through nanometer-sized voids ordered within the layers of crystalline carbon nitride with a polytriazine imide structure. The transport mechanism involves a sequence of molecular orientation reversals directed by hydrogen-bonding interactions as the neutral molecules traverse the interlayer gap and pass through the intralayer voids that show similarities with the transport of water through transmembrane aquaporin channels in biological systems. The results suggest that nanoporous layered carbon nitrides can be useful for developing high-performance membranes.

Electrocatalytic oxygen reduction reaction (ORR) has been intensively studied for environmentally benign applications. However, insufficient understanding of ORR 2 e−‐pathway mechanism at the atomic level inhibits rational design of catalysts with both high activity and selectivity, causing concerns including catalyst degradation due to Fenton reaction or poor efficiency of H2O2 electrosynthesis. Herein we show that the generally accepted ORR electrocatalyst design based on a Sabatier volcano plot argument optimises activity but is unable to account for the 2 e−‐pathway selectivity. Through electrochemical and operando spectroscopic studies on a series of CoNx/carbon nanotube hybrids, a construction‐driven approach based on an extended “dynamic active site saturation” model that aims to create the maximum number of 2 e− ORR sites by directing the secondary ORR electron transfer towards the 2 e− intermediate is proven to be attainable by manipulating O2 hydrogenation kinetics.

This is the first communication of micropropagation system for Inula germanica using seedling explants germinated in vitro. The development of this system gives the possibility of future reintroduction of I. germanica providing a way to stabilize or re-establish its population. Shoot tips and fragments of cotyledons, hypocotyls and roots were isolated from ten-day-old seedlings. Explants were put on MS medium containing 1.0 mg l ) at 26 ± 1 °C. The highest percentage of shoot organogenesis (83.3%) was recorded for hypocotyl, while the highest average number of shoots per explant (12.0) was recorded for shoot tips. In subsequent subcultures, multiplication rate decreased to 3.0-4.9 shoots per explant. Less than 19% shoots were able to root on the solid medium without auxins. The highest rooting efficiency (69.3%) was recorded for solid medium supplemented with indolebutyric acid, but growth of roots was inhibited. The percentage of rooted shoots (62.2%) and number of roots per shoot (2.4 per shoot) into the liquid medium were comparable to medium with 0.1 mg·l -1 indolebutyric acid. showing a positive impact on the process of acclimatization. The regenerated plants were able to flowering in the first year after acclimatization. Developed micropropagation system for I. germanica is efficient and can be a useful tool for the active protection of this species.

The functionalisation of two-dimensional materials is key to modify their properties and facilitate assembly into functional devices. Here, new reactions have been proposed to modify crystalline two-dimensional carbon nitrides of polytriazine imide structure. Both amine alkylation and aryl-nitrene-based reactions have been explored computationally and with exploratory synthetic trials. The approach illustrates that alkylation is unfavourable, particularly at basal-plane sites. In contrast, while initial trial reactions were inconclusive, the radical-addition of nitrenes is shown to be energetically favourable, with a preference for functionalising sheet edges to minimise steric effects.

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