Engineering 2D spin networks by on-surface encapsulation of azafullerene radicals in nanotemplates.

We present an efficient strategy for on-surface engineering of organic metal-free supramolecular complexes with long-term spin protection. By vacuum deposition of azafullerene (CN) monomers on a pre-deposited template layer of [10]cycloparaphenylene ([10]CPP) nanohoops on Au(111) surface we exploit the molecular shape matching between the CN and [10]CPP for the azafullerene encapsulation with nanohoops in a guest-host complexation geometry. CN⊂[10]CPP supramolecular complexes self-assemble into an extended two-dimensional hexagonal lattice yielding a high density network of stable spin-1/2 radicals.

Seeding the vertical growth of laterally coherent coordination polymers on the rutile-TiO(110) surface.

Coordination polymers may be synthesized by linear bridging ligands to metal ions with conventional chemistry methods ( in solution). Such complexes can be hardly brought onto a substrate with the chemical, spatial and geometrical homogeneity required for device integration. Instead, we follow an synthesis approach, where the anchoring points are provided by a monolayer of metal(II)-tetraphenylporphyrin (M-TPP, M = Cu, Zn, Co) grown in on the rutile-TiO(110) surface.

Oxygen-Promoted on-Surface Synthesis of Polyboroxine Molecules.

We present a protocol for the on-surface synthesis of polyboroxine molecules derived from boroxine molecules precursors. This process is promoted by oxygen species present on the Au(111) surface: oxygen atoms facilitate the detachment of naphthalene units of trinaphthyl-boroxine molecules and bridge two unsaturated boroxine centers to form a boroxine-O-boroxine chemical motif. X-ray spectroscopic characterization shows that, as the synthesis process proceeds, it progressively tunes the electronic properties of the interface, thus providing a promising route to control the electron level alignment.

Charge Transfer and Orbital Reconstruction at an Organic-Oxide Interface.

The two-dimensional electron system (2DES) located at the surface of strontium titanate (STO) and at several other STO-based interfaces has been an established platform for the study of novel physical phenomena since its discovery. Here we report how the interfacing of STO and tetracyanoquinodimethane (TCNQ) results in a charge transfer that depletes the number of free carriers at the STO surface, with a strong impact on its electronic structure. Our study paves the way for efficient tuning of the electronic properties, which promises novel applications in the framework of oxide/organic-based electronics.

Self-Assembled Monolayers of N-Heterocyclic Olefins on Au(111).

Self-assembled monolayers (SAMs) of N-heterocyclic olefins (NHOs) have been prepared on Au(111) and their thermal stability, adsorption geometry, and molecular order were characterized by X-ray photoelectron spectroscopy, polarized X-ray absorption spectroscopy, scanning tunneling microscopy (STM), and density functional theory (DFT) calculations. The strong σ-bond character of NHO anchoring to Au induced high geometrical flexibility that enabled a flat-lying adsorption geometry via coordination to a gold adatom. The flat-lying adsorption geometry was utilized to further increase the surface interaction of the NHO monolayer by backbone functionalization with methyl groups that induced high thermal stability and a large impact on work-function values, which outperformed that of N-heterocyclic carbenes.

Inequivalent Solvation Effects on the N 1s Levels of Self-Associated Melamine Molecules in Aqueous Solution.

This work shows how the N 1s photoemission (PE) spectrum of self-associated melamine molecules in aqueous solution has been successfully rationalized using an integrated computational approach encompassing classical metadynamics simulations and quantum calculations based on density functional theory (DFT). The first approach allowed us to describe interacting melamine molecules in explicit waters and to identify dimeric configurations based on π-π and/or H-bonding interactions. Then, N 1s binding energies (BEs) and PE spectra were computed at the DFT level for all structures both in the gas phase and in an implicit solvent.

Comet assay in Aegla platensis (Decapoda: Anomura) using a non-lethal hemolymph field sampling for in situ monitoring of freshwater genotoxicity.

This study aimed to apply the comet assay on Aegla platensis crabs as a suitable non-destructive approach for in situ monitoring of freshwater genotoxicity. Animals were captured during four sampling periods in a stream under minor anthropogenic impacts in Southern Brazil. Crabs were captured with a hand net, then the hemolymph samples were collected, and the animals were released into the stream after a 20-min recovery time.

Treated tannery effluent and its impact on the receiving stream water: physicochemical characterization and cytogenotoxic evaluation using the Allium cepa test.

Tanneries are considered some of the most polluting industries due to the heavy use of toxic compounds, most of which are released into water bodies, thus exerting adverse effects on aquatic biota. However, the effects on organisms of treated effluents when released into the natural environment are rarely evaluated. This study aims to assess the physicochemical parameters of a tannery effluent after treatment (TE) at a Common Effluent Treatment Plant as well as the water of the receiving stream and to evaluate cytogenotoxic effects in Allium cepa.

On surface chemical reactions of free-base and titanyl porphyrins with r-TiO(110): a unified picture.

In this Perspective we present a comprehensive study of the multiple reaction products of metal-free porphyrins (2H-Ps) in contact with the rutile TiO(110) surface. In the absence of peripheral functionalization with specific linkers, the porphyrin adsorption is driven by the coordination of the two pyrrolic nitrogen atoms of the macrocycle to two consecutive oxygen atoms of the protruding O rows hydrogen bonding. This chemical interaction favours the iminic nitrogen uptake of hydrogen from near surface layers at room temperature, thus yielding a stable acidic porphyrin (4H-P).

Orbital Mapping of Semiconducting Perylenes on Cu(111).

Semiconducting O-doped polycyclic aromatic hydrocarbons constitute a class of molecules whose optoelectronic properties can be tailored by acting on the π-extension of the carbon-based frameworks and on the oxygen linkages. Although much is known about their photophysical and electrochemical properties in solution, their self-assembly interfacial behavior on solid substrates has remained unexplored so far. In this paper, we have focused our attention on the on-surface self-assembly of O-doped bi-perylene derivatives.

Carbon Nanotubes Substrates Alleviate Pro-Calcific Evolution in Porcine Valve Interstitial Cells.

The quest for surfaces able to interface cells and modulate their functionality has raised, in recent years, the development of biomaterials endowed with nanocues capable of mimicking the natural extracellular matrix (ECM), especially for tissue regeneration purposes. In this context, carbon nanotubes (CNTs) are optimal candidates, showing dimensions and a morphology comparable to fibril ECM constituents. Moreover, when immobilized onto surfaces, they demonstrated outstanding cytocompatibility and ease of chemical modification with ad hoc functionalities.

Self-Metalation of Porphyrins at the Solid-Gas Interface.

Self-metalation is a promising route to include a single metal atom in a tetrapyrrolic macrocycle in organic frameworks supported by metal surfaces. The molecule-surface interaction may provide the charge transfer and the geometric distortion of the molecular plane necessary for metal inclusion. However, at a metal surface the presence of an activation barrier can represent an obstacle that cannot be compensated by a higher substrate temperature without affecting the layer integrity.

Wavy graphene sheets from electrochemical sewing of corannulene.

The presence of non-hexagonal rings in the honeycomb carbon arrangement of graphene produces rippled graphene layers with valuable chemical and physical properties. In principle, a bottom-up approach to introducing distortion from planarity of a graphene sheet can be achieved by careful insertion of curved polyaromatic hydrocarbons during the growth of the lattice. Corannulene, the archetype of such non-planar polyaromatic hydrocarbons, can act as an ideal wrinkling motif in 2D carbon nanostructures.

Tailoring surface-supported water-melamine complexes by cooperative H-bonding interactions.

The water-splitting photo-catalysis by carbon nitride heterocycles has been the subject of recent theoretical investigations, revealing a proton-coupled electron transfer (PCET) reaction from the H-bonded water molecule to the CN-heterocycle. In this context, a detailed characterization of the water-catalyst binding configuration becomes mandatory in order to validate and possibly improve the theoretical modeling. To this aim, we built a well-defined surface-supported water/catalyst interface by adsorbing water under ultra-high vacuum (UHV) conditions on a monolayer of melamine grown on the Cu(111) surface.

Enhanced ambient stability of exfoliated black phosphorus by passivation with nickel nanoparticles.

Since its discovery, the environmental instability of exfoliated black phosphorus (2D bP) has emerged as a challenge that hampers its wide application in chemistry, physics, and materials science. Many studies have been carried out to overcome this drawback. Here we show a relevant enhancement of ambient stability in few-layer bP decorated with nickel nanoparticles as compared to pristine bP.

Infectious risk in ostomy patient: the role of nursing competence.

Background And Aim Of The Work: The risk of peristomal infections in ostomy patients is well documented in the literature. The nurse and the stoma therapist play a fundamental role in the management and prevention of ostomy-related infections. The present research aims to investigate, across the different phases of the nursing process, the level and characteristics of nursing expertise and highlight their impact on reducing infectious risk in ostomy patients.

Electronic structure of MAPbI and MAPbCl: importance of band alignment.

Since their first appearance, organic-inorganic perovskite absorbers have been capturing the attention of the scientific community. While high efficiency devices highlight the importance of band level alignment, very little is known on the origin of the strong n-doping character observed in the perovskite. Here, by means of a highly accurate photoemission study, we shed light on the energy alignment in perovskite-based devices.

Transparent carbon nanotubes promote the outgrowth of enthorino-dentate projections in lesioned organ slice cultures.

The increasing engineering of carbon-based nanomaterials as components of neuroregenerative interfaces is motivated by their dimensional compatibility with subcellular compartments of excitable cells, such as axons and synapses. In neuroscience applications, carbon nanotubes (CNTs) have been used to improve electronic device performance by exploiting their physical properties. Besides, when manufactured to interface neuronal networks formation in vitro, CNT carpets have shown their unique ability to potentiate synaptic networks formation and function.

Enhanced selectivity of target gas molecules through a minimal array of gas sensors based on nanoparticle-decorated SWCNTs.

An array of five sensors, based on carbon nanotubes (CNT) functionalized with nanoparticles of Au, TiO, ITO, and Si has been fabricated and exposed to a selected series of target gas molecules (NH, NO, HS, HO, benzene, ethanol, acetone, 2-propanol, sodium hypochlorite, and several combinations of two gases). The results of principal component analysis (PCA) of the experimental data show that this array of sensors is able to detect different target gas and to discriminate each molecule in the 2D PCA parameters space. In particular, the possibility to include in the array a humidity sensor significantly increases the capability to discriminate the response to volatile organic compounds (VOCs), even though VOCs usually react with CNTs less than NO or NH.

Carbon Nanotubes, Directly Grown on Supporting Surfaces, Improve Neuronal Activity in Hippocampal Neuronal Networks.

Carbon nanotube (CNT)-modified surfaces unequivocally demonstrate their biocompatibility and ability to boost the electrical activity of neuronal cells cultured on them. Reasons for this effect are still under debate. However, the intimate contact at the membrane level between these thready nanostructures and cells, in combination with their unique electrical properties, seems to play an important role.

Improved recovery time and sensitivity to H and NH at room temperature with SnO vertical nanopillars on ITO.

Nanostructured SnO is a promising material for the scalable production of portable gas sensors. To fully exploit their potential, these gas sensors need a faster recovery rate and higher sensitivity at room temperature than the current state of the art. Here we demonstrate a chemiresistive gas sensor based on vertical SnO nanopillars, capable of sensing < 5 ppm of H at room temperature and 10 ppt at 230 °C.

DNA Damage in Wistar Rats Exposed to Organophosphate Pesticide Fenthion.

In the last several decades, exposure to pesticides has become a concern to environmental and human health. Many pesticides are environmentally persistent and are characterized by varying degrees of toxicity and adverse effects, including DNA damage. The present study was undertaken to evaluate the genotoxic potential of organophosphate pesticide fenthion in Wistar rats, as assessed by the comet assay.

Publisher Correction: Multi-orbital charge transfer at highly oriented organic/metal interfaces.

The original version of this Article contained an error in the spelling of the author Claus Michael Schneider, which was incorrectly given as Claus Michael Schneidery. This has now been corrected in both the PDF and HTML versions of the Article.

Multi-orbital charge transfer at highly oriented organic/metal interfaces.

The molecule-substrate interaction plays a key role in charge injection organic-based devices. Charge transfer at molecule-metal interfaces strongly affects the overall physical and magnetic properties of the system, and ultimately the device performance. Here, we report theoretical and experimental evidence of a pronounced charge transfer involving nickel tetraphenyl porphyrin molecules adsorbed on Cu(100).