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On-surface synthesis of two-dimensional polymers is a useful strategy for designing the lattice, orbital and spin symmetries of materials, but controlling their layer stacking remains challenging. Now, a method to synthesize bilayer two-dimensional covalent organic frameworks at a liquid–substrate interface through monomer condensation has been developed; large-area moiré superlattices emerge from the twisted bilayer stacking.

Electrons from the tip of a scanning tunnelling microscope can be used to drive and monitor the directional rotation of a single molecule on a metal surface.

The self-assembly of molecules into porous two-dimensional networks on surfaces has been well studied in recent years, but now the concept has been extended to three dimensions with a little help from fullerene molecules.

Covalent modification is an essential chemical method for altering the physicochemical properties of material interfaces. Here, the authors show that the no-slip conditions in microfluidic devices grant spatiotemporal control over molecular grafting.

Ultrathin metallic films are most often fabricated by atomic or molecular beam epitaxy under ultrahigh vacuum conditions, where it is difficult to control deposition and growth. Here, the authors describe a wet deposition method, using solution-borne gold nanocluster precursors, to regulate growth of atomically flat gold nanoislands on a surface.

In situ scanning tunnelling microscopy reveals the dynamic nature of the early stages of two-dimensional (2D) polymer formation and crystallization at the solid–liquid interface.

One of the most dramatic effects of supramolecular assembly is the generation of homochirality in near-racemic systems. Here the authors rationalize the chiral amplification mechanism with a combined scanning tunneling microscopy and modelling study of surface-grown enantiomerically unbalanced supramolecular bilayers.

A scanning tunnelling microscope has been used to image multistep chemical reactions at a solid/liquid interface with single-molecule resolution. On reacting Mn(III) porphyrins with either O₂ or a single oxygen donor, at least four distinct reaction intermediates and products were detected and their interconversion could be observed in real space and real time.

Lattice anchoring, in its varied forms, has proven effective at regulating the energetics of metastable phases of polymorphic crystals. Here, the authors utilize top-down photolithography to embed a tessellating 3D interfacial network into otherwise-unstable CsPbI₃ perovskite thin films and devices, stabilizing the perovskite phase.

The formation of homochiral supramolecular networks at solution–solid interfaces typically relies on the soldier-and-sergeant approach, in which a small amount of chiral modifier defines the handedness of the network. Now, judicious choice of the sergeant, solvent, temperature and concentration has enabled chiral induction pathways to be controlled so that a homochiral surface of either handedness can be assembled from the same system.

The low dielectric constants and high porosity of MOFs are of interest for applications in electronics and sensors, but patterning techniques for these materials are in their infancy. Here, direct X-ray and electron-beam lithography at sub-50-nm resolution are reported that leave porosity and crystallinity intact.

The authors show that thin films of microporous metal–organic frameworks can be deposited on a broad range of substrates and on high-aspect-ratio features by means of chemical vapour deposition.

Liquid-phase-processable graphene nanoribbons (GNRs) over 200 nm long and with well-defined structures have now been synthesized by a bottom-up method, and are found to have a large optical bandgap of 1.88 eV. Scanning probe microscopy revealed highly ordered self-assembled monolayers of the GNRs, and the high intrinsic charge-carrier mobility of individual ribbons was characterized by terahertz spectroscopy.

The generation of two-dimensional homochiral porous molecular networks at the liquid–solid interface is described. Using scanning tunnelling microscopy, the formation of homochiral porous networks was observed both from solutions of homochiral molecules and from solutions of achiral molecules in the presence of a small amount of a chiral modifier.

The strong electric field between the tip of a scanning tunneling microscope and graphite has been used to modulate the two-dimensional polymerization of aryl boronic acids. Here, the authors study the influence of solvent choice and monomer concentration on the electric field-mediated polymerization and depolymerization of a boroxine-based 2D polymer on graphite.

Switching of static friction and adhesion of a liquid drop on a corrugated solid boron nitride surface is linked to the intercalation of hydrogen, which changes the electric field of in-plane dipole rings and thus reduces the adsorption energy.