Molecular thin films, such as self-assembled monolayers (SAMs), offer the possibility of translating the optimised thermophysical and electrical properties of high-Seebeck-coefficient single molecules to scalable device architectures. However, for many scanning probe-based approaches attempting to characterise such SAMs, there remains a significant challenge in recovering single-molecule equivalent values from large-area films due to the intrinsic uncertainty of the probe-sample contact area coupled with film damage caused by contact forces. Here we report a new reproducible non-destructive method for probing the electrical and thermoelectric (TE) properties of small assemblies (10-10(3)) of thiol-terminated molecules arranged within a SAM on a gold surface, and demonstrate the successful and reproducible measurements of the equivalent single-molecule electrical conductivity and Seebeck values. We have used a modified thermal-electric force microscopy approach, which integrates the conductive-probe atomic force microscope, a sample positioned on a temperature-controlled heater, and a probe-sample peak-force feedback that interactively limits the normal force across the molecular junctions. The experimental results are interpreted by density functional theory calculations allowing quantification the electrical quantum transport properties of both single molecules and small clusters of molecules. Significantly, this approach effectively eliminates lateral forces between probe and sample, minimising disruption to the SAM while enabling simultaneous mapping of the SAMs nanomechanical properties, as well as electrical and/or TE response, thereby allowing correlation of the film properties.

Alkanethiol molecules with planar aromatic head groups were synthesised and assembled on gold surfaces. The conductance properties of the resulting monolayers were measured using conductive atomic force microscopy with Pt and graphene coated tips.

AbstractAs the field of molecular‐scale electronics matures and the prospect of devices incorporating molecular wires becomes more feasible, it is necessary to progress from the simple anchor groups used in fundamental conductance studies to more elaborate anchors designed with device stability in mind. This study presents a series of oligo(phenylene‐ethynylene) wires with one tetrapodal anchor and a phenyl or pyridyl head group. The new anchors are designed to bind strongly to gold surfaces without disrupting the conductance pathway of the wires. Conductive probe atomic force microscopy (cAFM) was used to determine the conductance of self‐assembled monolayers (SAMs) of the wires in Au–SAM–Pt and Au–SAM–graphene junctions, from which the conductance per molecule was derived. For tolane‐type wires, mean conductances per molecule of up to 10−4.37 G0 (Pt) and 10−3.78 G0 (graphene) were measured, despite limited electronic coupling to the Au electrode, demonstrating the potential of this approach. Computational studies of the surface binding geometry and transport properties rationalise and support the experimental results.

Porous carbon could not be designed on a molecular level until now. In their Communication on page 11952 ff., T. Ben, A. Trewin, and co-workers report an organic synthetic strategy to attain porous carbon by design on the molecular level. This sp–sp3 hybridized porous carbon, OSPC-1, is a highly promising anode material for lithium-ion batteries with high capacity and resistance to dendrite formation. This method has the potential to extend research frontiers to a new family of porous carbon materials.

We report the first organically synthesized sp-sp3 hybridized porous carbon, OSPC-1. This new carbon shows electron conductivity, high porosity, the highest uptake of lithium ions of any carbon material to-date, and the ability to inhibit dangerous lithium dendrite formation. The new carbon exhibits exceptional potential as anode material for lithium-ion batteries (LIBs) with high capacity, excellent rate capability, long cycle life, and potential for improved safety performance.

Poröser Kohlenstoff konnte bisher noch nicht auf molekularer Ebene entworfen werden. In ihrer Zuschrift auf S. 12128 berichten T. Ben, A. Trewin und Mitarbeiter nun über eine entsprechende organische Synthese eines porösen Kohlenstoffs mit sp-sp3-Hybridisierung. Ihr Produkt, OSPC-1, ist ein vielversprechendes Anodenmaterial für Lithiumionenbatterien mit hoher Kapazität und unterdrückter Dendritenbildung. Die Methode könnte eine neue Richtung auf dem Forschungsfeld poröser Kohlenstoffmaterialien weisen.