One-atom-thick crystals are impermeable to atoms and molecules, but hydrogen ions (thermal protons) penetrate through them. We show that monolayers of graphene and boron nitride can be used to separate hydrogen ion isotopes. Using electrical measurements and mass spectrometry, we found that deuterons permeate through these crystals much slower than protons, resulting in a separation factor of ≈10 at room temperature. The isotope effect is attributed to a difference of ≈60 milli-electron volts between zero-point energies of incident protons and deuterons, which translates into the equivalent difference in the activation barriers posed by two-dimensional crystals. In addition to providing insight into the proton transport mechanism, the demonstrated approach offers a competitive and scalable way for hydrogen isotope enrichment.

The formation and use of iminyl radicals in novel and divergent hydroimination and iminohydroxylation cyclization reactions has been accomplished through the design of a new class of reactive O-aryl oximes. Owing to their low reduction potentials, the inexpensive organic dye eosin Y could be used as the photocatalyst of the organocatalytic hydroimination reaction. Furthermore, reaction conditions for a unique iminohydroxylation were identified; visible-light-mediated electron transfer from novel electron donor–acceptor complexes of the oximes and Et3N was proposed as a key step of this process.

The liquid-liquid interface provides a molecularly sharp, defect free focal plane for the assembly of solid materials. In this article we discuss the various materials which have been successfully assembled at the liquid/liquid interface such as metallic nanoparticles, Janus particles and carbon nanomaterials. Strategies to induce particle assembly include manipulation of surface chemistry, surface charge and potential control. Liquid/liquid assembly can be exploited to synthesise materials in situ and template preformed structures. We go on to discuss the difficulties encountered when attempting to fully understand the structure of assemblies present at the liquid/liquid interface and the development of experimental techniques to elucidate information about the structure, stability, chemical composition, and reactivity of interfacial assemblies.

Zum Ende des Sommers nimmt die Zahl der Insekten in Wald und Flur deutlich ab. Nur noch wenige Schmetterlinge gaukeln über blütenarme Wiesen. Doch einige häufige Nachtfalter‐Raupen sind gerade im September und Oktober kaum zu übersehen und ermöglichen somit interessante Beobachtungen im Herbst.

ParagraphFabrics, materials consisting of layers of woven fibres, are some of the most important materials in everyday life. 1 Previous nanoscale weaves [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16] include isotropic crystalline covalent organic frameworks (COFs) 12-14 that feature rigid helical strands interlaced in all three dimensions rather than the 2D 17,18 layers of flexible woven strands that give conventional textiles their characteristic flexibility, thinness, anisotropic strength and porosity. A supramolecular 2D kagome weave 15 and a single-layer, surfacesupported, interwoven 2D polymer 16 have also been reported. However, despite being proposed on a number of occasions, [19][20][21][22][23] the direct, bottom-up, assembly of molecular building blocks into linear organic polymer chains woven in two-dimensions has remained elusive. Here we demonstrate that anion and metal ion template woven molecular 'tiles' can be tessellated into a material consisting of alternating aliphatic and aromatic segmented polymer strands, interwoven within discrete layers. Connections between slowly precipitating pre-woven grids, followed by the removal of the ion templates, results in a wholly-organic molecular material that forms as stacks and clusters of thin sheets, each sheet up to 100s of m long and wide but only ~4 nm thick, in which warp and weft single-chain polymer strands remain associated through periodic mechanical entanglements within each sheet. Atomic force (AFM) and scanning electron (SEM) microscopies show clusters and, occasionally, isolated individual sheets that following demetallation have slid apart from others they were stacked with during the tessellation and polymerisation process. The layered 2D molecularly woven material has long-range order, is birefringent, twice as stiff as the constituent linear polymer, and delaminates and tears along well-defined lines in the manner of a macroscopic textile. When incorporated into a polymer-supported membrane it acts as a net, slowing the passage of large ions while letting smaller ions through. The findings open up new opportunities and research directions for molecular materials made of flexible polymer chains mechanically woven at the nanoscale in two (or three) dimensions.

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Poor cycling stability and mechanistic controversies have hindered the wider application of rechargeable aqueous Zn–MnO2 batteries. Herein, direct evidence was provided of the importance of Mn2+ in this type of battery by using a bespoke cell. Without pre‐addition of Mn2+, the cell exhibited an abnormal discharge–charge profile, meaning it functioned as a primary battery. By adjusting the Mn2+ content in the electrolyte, the cell recovered its charging ability through electrodeposition of MnO2. Additionally, a dynamic pH variation was observed during the discharge–charge process, with a precipitation of Zn4(OH)6(SO4)⋅5H2O buffering the pH of the electrolyte. Contrary to the conventional Zn2+ intercalation mechanism, MnO2 was first converted into MnOOH, which reverted to MnO2 through disproportionation, resulting in the dissolution of Mn2+. The charging process occurred by the electrodeposition of MnO2, thus improving the reversibility through the availability of Mn2+ ions in the solution.