Two-Dimensional Photosensitizer Nanosheets via Low-Energy Electron Beam Induced Cross-Linking of Self-Assembled Ru Polypyridine Monolayers.

Artificial photosynthesis for hydrogen production is an important element in the search for green energy sources. The incorporation of photoactive units into mechanically stable 2D materials paves the way toward the realization of ultrathin membranes as mimics for leaves. Here we present and compare two concepts to introduce a photoactive Ru polypyridine complex into ≈1 nm thick carbon nanomembranes (CNMs) generated by low-energy electron irradiation induced cross-linking of aromatic self-assembled monolayers.

Photoactive ultrathin molecular nanosheets with reversible lanthanide binding terpyridine centers.

In recent years, functional molecular nanosheets have attracted much attention in the fields of sensors and energy storage. Here, we present an approach for the synthesis of photoactive metal-organic nanosheets with ultimate molecular thickness. To this end, we apply low-energy electron irradiation induced cross-linking of 4'-(2,2':6',2''-terpyridine-4'-yl)-1,1'-biphenyl-4-thiol self-assembled monolayers on gold to convert them into functional ∼1 nm thick carbon nanomembranes possessing the ability to reversibly complex lanthanide ions (Ln-CNMs).

In situ photothermal deflection spectroscopy revealing intermolecular interactions upon self-assembly of dye monolayers.

We demonstrate the potential of photothermal deflection spectroscopy (PDS) to study the self-assembly of dye monolayers in situ. Beyond the determination of adsorption kinetics at specific wavelengths, PDS gains its strength from yielding UV-vis absorptance spectra of SAMs in situ, unaffected by scattering, from which supramolecular interactions can be deduced.

Self-Assembled Graphene/MWCNT Bilayers as Platinum-Free Counter Electrode in Dye-Sensitized Solar Cells.

We describe the preparation and properties of bilayers of graphene- and multi-walled carbon nanotubes (MWCNTs) as an alternative to conventionally used platinum-based counter electrode for dye-sensitized solar cells (DSSC). The counter electrodes were prepared by a simple and easy-to-implement double self-assembly process. The preparation allows for controlling the surface roughness of electrode in a layer-by-layer deposition.

Autonomous Supramolecular Interface Self-Healing Monitored by Restoration of UV/Vis Absorption Spectra of Self-Assembled Thiazole Layers.

Longevity of complex organic devices critically depends on the supramolecular integrity of the constituting layers and interfaces. Because the latter are soft matter, they can structurally respond to perturbation of their supramolecular structure by relaxing back to a thermodynamically favorable state. To use this response for self-healing of optoelectronically active layers and particularly interfaces, the degraded dyes in these layers need to be exchanged with non-degraded ones.

Photoannealing of Merocyanine Aggregates.

In this work we elucidate the fundamental difference between aggregate formation of donor-π-acceptor merocyanines in their electronic ground and excited states. While increasing the π-bridge size favors formation of π-stacked aggregates in the dark, irradiation with visible light causes reorientation of the dyes to form prototype H-aggregates with compensating dipole moments. This photoannealing changes the supramolecular structure and its UV-vis spectroscopic properties dramatically, thus being of importance for the function of active layers composed of these dyes.

On the Control of Chromophore Orientation, Supramolecular Structure, and Thermodynamic Stability of an Amphiphilic Pyridyl-Thiazol upon Lateral Compression and Spacer Length Variation.

The supramolecular structure essentially determines the properties of organic thin films. Therefore, it is of utmost importance to understand the influence of molecular structure modifications on supramolecular structure formation. In this article, we demonstrate how to tune molecular orientations of amphiphilic 4-hydroxy thiazole derivatives by means of the Langmuir-Blodgett (LB) technique and how this depends on the length of an alkylic spacer between the thiazole chromophore and the polar anchor group.

Absorption and Fluorescence Features of an Amphiphilic meso-Pyrimidinylcorrole: Experimental Study and Quantum Chemical Calculations.

Corroles are emerging as an important class of macrocycles with numerous applications because of their peculiar photophysical and metal chelating properties. meso-Pyrimidinylcorroles are easily deprotonated in certain solvents, which changes their absorption and emission spectra as well as their accessible supramolecular structures. To enable control over the formation of supramolecular structures, the dominant corrole species, i.

Controlling Electronic Transitions in Fullerene van der Waals Aggregates via Supramolecular Assembly.

Morphologies crucially determine the optoelectronic properties of organic semiconductors. Therefore, hierarchical and supramolecular approaches have been developed for targeted design of supramolecular ensembles of organic semiconducting molecules and performance improvement of, e.g.

Photometric Detection of Nitric Oxide Using a Dissolved Iron(III) Corrole as a Sensitizer.

The potential of an iron(III) corrole complex for use in the detection of nitric oxide (NO) was investigated. The reversible conversion of an dissolved iron(III) corrole to its corresponding nitrosyl complex using gaseous nitric oxide was monitored by UV/Vis spectroscopy. The spectral differences between both coordination compounds were used to determine photometrically small amounts of nitric oxide in the sub-parts-per-million range.

Photometric Detection of Nitric Oxide Using a Dissolved Iron(III) Corrole as a Sensitizer.

Invited for this month's cover are the collaborating groups of Dr. Martin Presselt from Friedrich Schiller University Jena, Germany and Prof. Zeev Gross from Technion-Israel Institute of Technology, Haifa, Israel.