Solution Atomic Layer Deposition of Smooth, Continuous, Crystalline Metal-Organic Framework Thin Films.

For the first time, a procedure has been established for the growth of surface-anchored metal-organic framework (SURMOF) copper(II) benzene-1,4-dicarboxylate (Cu-BDC) thin films of thickness control with single molecule accuracy. For this, we exploit the novel method solution atomic layer deposition (sALD). The sALD growth rate has been determined at 4.

A Geometrically Well-Defined and Systematically Tunable Experimental Model to Transition from Planar to Mesoporous Perovskite Solar Cells.

A series of perovskite solar cells with systematically varying surface area of the interface between n-type electron conducting layer (TiO) and perovskite are prepared by using an ordered array of straight, cylindrical nanopores generated by anodizing an aluminum layer evaporated onto a transparent conducting electrode. A series of samples with pore length varied from 100 to 500 nm are compared to each other and complemented by a classical planar cell and a mesoporous counterpart. All samples are characterized in terms of morphology, chemistry, optical properties, and performance.

Stabilizing an ultrathin MoS layer during electrocatalytic hydrogen evolution with a crystalline SnO underlayer.

Amorphous MoS has been investigated abundantly as a catalyst for hydrogen evolution. Not only its performance but also its chemical stability in acidic conditions have been reported widely. However, its adhesion has not been studied systematically in the electrochemical context.

Erratum: Fast Domain Wall Motion Governed by Topology and Œrsted Fields in Cylindrical Magnetic Nanowires [Phys. Rev. Lett. 123, 217201 (2019)].

This corrects the article DOI: 10.1103/PhysRevLett.123.

Solid state interdigitated SbS based TiO nanotube solar cells.

TiO nanotubes generated by anodization of metallic titanium sputter-coated on indium tin oxide (ITO) substrates are used as a conductive scaffold for all solid-state SbS-sensitized extremely thin absorber (ETA) solar cells. A blocking layer of TiO placed between Ti and ITO in combination with optimized Ti deposition and anodization conditions enables the formation of crack-free layers of straight, cylindrical TiO nanotubes of tunable length and diameter. ALD (atomic layer deposition) is subsequently used to coat this substrate conformally with a highly pure SbS light absorber layer under an inert atmosphere.

Fast Domain Wall Motion Governed by Topology and Œrsted Fields in Cylindrical Magnetic Nanowires.

While the usual approach to tailor the behavior of condensed matter and nanosized systems is the choice of material or finite-size or interfacial effects, topology alone may be the key. In the context of the motion of magnetic domain walls (DWs), known to suffer from dynamic instabilities with low mobilities, we report unprecedented velocities >600  m/s for DWs driven by spin-transfer torques in cylindrical nanowires made of a standard ferromagnetic material. The reason is the robust stabilization of a DW type with a specific topology by the Œrsted field associated with the current.

Transmission XMCD-PEEM imaging of an engineered vertical FEBID cobalt nanowire with a domain wall.

Using focused electron-beam-induced deposition, we fabricate a vertical, platinum-coated cobalt nanowire with a controlled three-dimensional structure. The latter is engineered to feature bends along the height: these are used as pinning sites for domain walls, which are obtained at remanence after saturation of the nanostructure in a horizontally applied magnetic field. The presence of domain walls is investigated using x-ray magnetic circular dichroism (XMCD) coupled to photoemission electron microscopy (PEEM).

Synthesis, Characterization, and Properties of Iron(II) Spin-Crossover Molecular Photoswitches Functioning at Room Temperature.

Spin-crossover molecular switches [Fe(HB(pz))L] (L = novel phenanthroline-based ligands featuring photochromic diarylethene units; pz = 1-pyrazolyl) were synthesized and thoroughly characterized by variable-temperature X-ray crystallography, Mössbauer spectroscopy, and magnetic measurements. The effect of substituents introduced into the phenanthroline backbone (L2) and into the photochromic diarylethene unit (L3) on photophysical properties of metal-free ligands and spin-crossover iron(II) complexes 2 and 3, respectively, were investigated in detail. Both ligands and complexes could be switched with light in solution at room temperature.

Design Rules for Oxygen Evolution Catalysis at Porous Iron Oxide Electrodes: A 1000-Fold Current Density Increase.

Nanotubular iron(III) oxide electrodes are optimized for catalytic efficiency in the water oxidation reaction at neutral pH. The nanostructured electrodes are prepared from anodic alumina templates, which are coated with Fe O by atomic layer deposition. Scanning helium ion microscopy, X-ray diffraction, and Raman spectroscopy are used to characterize the morphologies and phases of samples submitted to various treatments.

Photochemical Energy Storage and Electrochemically Triggered Energy Release in the Norbornadiene-Quadricyclane System: UV Photochemistry and IR Spectroelectrochemistry in a Combined Experiment.

The two valence isomers norbornadiene (NBD) and quadricyclane (QC) enable solar energy storage in a single molecule system. We present a new photoelectrochemical infrared reflection absorption spectroscopy (PEC-IRRAS) experiment, which allows monitoring of the complete energy storage and release cycle by in situ vibrational spectroscopy. Both processes were investigated, the photochemical conversion from NBD to QC using the photosensitizer 4,4'-bis(dimethylamino)benzophenone (Michler's ketone, MK) and the electrochemically triggered cycloreversion from QC to NBD.

Energy Storage in Strained Organic Molecules: (Spectro)Electrochemical Characterization of Norbornadiene and Quadricyclane.

We have investigated the electrochemically triggered cycloreversion of quadricyclane (QC) to norbornadiene (NBD), a system that holds the potential to combine both energy storage and conversion in a single molecule. Unambiguous voltammetric traces are obtained for pure NBD and pure QC, the latter a strained polycyclic isomer of the former. The difference in redox potentials is smaller than the energy difference between the neutral molecules.

A large electrochemical setup for the anodization of aluminum towards highly ordered arrays of cylindrical nanopores.

A new electrochemical setup and the associated procedures for growing ordered anodic aluminum oxide pore arrays on large surfaces are presented. The typical size of the samples is 14 × 14 cm(2). The most crucial experimental parameters that allow for the stabilization of the high-field procedures are a very efficient cooling of sample and electrolyte, as well as the initial ramping up of the voltage at an accurately defined rate.

Synthesis and succinylation of subtilin-like lantibiotics are strongly influenced by glucose and transition state regulator AbrB.

Subtilin and the closely related entianin are class I lantibiotics produced by different subspecies of Bacillus subtilis. Both molecules are ribosomally synthesized peptide antibiotics with unusual ring structures. Subtilin-like lantibiotics develop strong antibiotic activities against various Gram-positive organisms with an efficiency similar to that of nisin from Lactococcus lactis.

Synthesis with perfect atom economy: generation of furan derivatives by 1,3-dipolar cycloaddition of acetylenedicarboxylates at cyclooctynes.

Cyclooctyne and cycloocten-5-yne undergo, at room temperature, a 1,3-dipolar cycloaddition with dialkyl acetylenedicarboxylates 1a,b to generate furan-derived short-lived intermediates 2, which can be trapped by two additional equivalents of 1a,b or alternatively by methanol, phenol, water or aldehydes to yield polycyclic products 3b-d, orthoesters 4a-c, ketones 5 or epoxides 6a,b, respectively. Treatment of bis(trimethylsilyl) acetylenedicarboxylate (1c) with cyclooctyne leads to the ketone 7 via retro-Brook rearrangement of the dipolar intermediate 2c. In all cases, the products are formed with perfect atom economy.

The First structure of a lantibiotic immunity protein, SpaI from Bacillus subtilis, reveals a novel fold.

Lantibiotics are peptide-derived antibiotics that inhibit the growth of Gram-positive bacteria via interactions with lipid II and lipid II-dependent pore formation in the bacterial membrane. Due to their general mode of action the Gram-positive producer strains need to express immunity proteins (LanI proteins) for protection against their own lantibiotics. Little is known about the immunity mechanism protecting the producer strain against its own lantibiotic on the molecular level.

Dronedarone prevents microcirculatory abnormalities in the left ventricle during atrial tachypacing in pigs.

Background And Purpose: Atrial fibrillation induces ischaemic microcirculatory flow abnormalities in the ventricle, contributing to the risk for acute coronary syndromes. We evaluated the effect of dronedarone on ventricular perfusion during rapid atrial pacing (RAP).

Experimental Approach: Coronary and fractional flow reserve (CFR/FFR) were measured in the left anterior descending artery in 29 pigs.

Entianin, a novel subtilin-like lantibiotic from Bacillus subtilis subsp. spizizenii DSM 15029T with high antimicrobial activity.

Lantibiotics, such as nisin and subtilin, are lanthionine-containing peptides that exhibit antimicrobial as well as pheromone-like autoinducing activity. Autoinduction is specific for each lantibiotic, and reporter systems for nisin and subtilin autoinduction are available. In this report, we used the previously reported subtilin autoinduction bioassay in combination with mass spectrometric analyses to identify the novel subtilin-like lantibiotic entianin from Bacillus subtilis subsp.