Polyol-Induced 100-Fold Enhancement of Bacterial Ice Nucleation Efficiency.

Ice-nucleating proteins (INPs) from bacteria like are among the most effective ice nucleators known. However, large INP aggregates with maximum ice nucleation activity (at approximately -2 °C) typically account for less than 1% of the overall ice nucleation activity in bacterial samples. This study demonstrates that polyols significantly enhance the assembly of INPs into large aggregates, dramatically improving bacterial ice nucleation efficiency.

Atmospheric Exposure Triggers Light-Induced Degradation in 2D Lead-Halide Perovskites.

Quasi-2D perovskites have been pivotal in recent efforts to stabilize perovskite solar cells. Despite the stability boost provided when these materials are introduced in perovskite solar cells, little is known about the intrinsic light and environmental stability of quasi-2D perovskites. In this study, we characterize the photostability of exfoliated quasi-2D perovskite single crystals in air using photoluminescence, infrared, X-ray fluorescence, and energy-dispersive X-ray spectroscopy.

Dynamic anti-correlations of water hydrogen bonds.

Water is characterized by strong intermolecular hydrogen bonds (H-bonds) between molecules. The two hydrogen atoms in one water molecule can form H-bonds of dissimilar length. Although intimately connected to water's anomalous properties, the details and the origins of the asymmetry have remained elusive.

Skeletal Nitrogen Functionalization of Isostructural 2D Conjugated MOFs for Enhancement of the Dual-Ion Storage Capacity.

Two-dimensional conjugated metal-organic frameworks (2D c-MOFs) are emerging as promising electrode materials for electrochemical energy storage devices. However, a viable path to realize superior dual-ion storage in 2D c-MOFs has remained elusive. Here, we report the synthesis of Cu(N-OHPTP) 2D c-MOFs (x=0,1,2; OHPTP=octahydroxyphenanthrotriphenylene) with precise aromatic carbon-nitrogen arrangements, based on the π-conjugated OHPTP ligand incorporated with one or two nitrogen atoms.

Acid-induced fluorescence enhancement of piperazinylphenyl-substituted nanographene.

A dibenzo[,]ovalene (DBOV) derivative bay-substituted with two piperazinylphenyl (PZP) groups (DBOV-PZP) was synthesized. Comprehensive investigations of its photophysical properties revealed acid-induced fluorescence enhancement through the protonation of PZP units, leading to the suppression of the photoinduced electron transfer. These results pave the way towards "turn-on" type nanographenes for biosensing and optical imaging.

High Charge Carrier Mobility in Porphyrin Nanoribbons.

Polydisperse edge-fused nickel(II) porphyrin nanoribbons have been synthesized by Yamamoto coupling followed by gold(III)-mediated fusion, with average degrees of polymerization of up to 37 repeat units (length 31 nm). Time-resolved optical-pump terahertz spectroscopy measurements indicate that photo-generated charge carriers have dc mobilities of up to 205 cm V s in these nanoribbons, exceeding the values previously reported for most other types of nanoribbon or π-conjugated polymer.

Temperature-dependent vibrational energy relaxation of hydrogen-bonded and free OD groups at the air-water interface.

Water interfaces play a crucial role in regulating interactions and energy flow. Vibrational sum-frequency generation (vSFG) spectroscopy provides structural and dynamic information on water molecules at interfaces. It has revealed, for instance, the presence of the hydrogen-bonded and free OH groups at the air-water interface.

Hierarchical assembly and environmental enhancement of bacterial ice nucleators.

Bacterial ice nucleating proteins (INPs) are exceptionally effective in promoting the kinetically hindered transition of water to ice. Their efficiency relies on the assembly of INPs into large functional aggregates, with the size of ice nucleation sites determining activity. Experimental freezing spectra have revealed two distinct, defined aggregate sizes, typically classified as class A and C ice nucleators (INs).

Flipping Water Orientation at the Surface of Water-in-Salt and Salt-in-Water Solutions.

Salt-in-water and water-in-salt mixtures are promising for battery applications and fine-tuning of room-temperature ionic liquid (RTIL) properties. Although critical processes take place at interfaces of these systems, including charge transfer and heterogeneous catalytic reactions, the microscopic interfacial structures remain unclear. Here, we apply heterodyne-detected sum-frequency generation spectroscopy to aqueous solutions of imidazolium-based RTILs to unveil the microscopic structure of the interfaces of these solutions with air.

The relationship between prognostic factors and patient satisfaction with performance of self-identified goals following interdisciplinary mild traumatic brain injury rehabilitation.

Background: Individuals with persistent symptoms following a mild traumatic brain injury (mTBI) demonstrate improved satisfaction with their performance of self-identified rehabilitation goals after completing a combined occupational therapy and physiotherapy group intervention. However, the relationship between factors associated with developing persistent symptoms following an mTBI and satisfaction with their performance of self-identified goals after completing an intervention are unknown.

Objective(s): To evaluate whether factors associated with developing persistent symptoms influence satisfaction with the performance of self-identified goals after completing a combined occupational therapy and physiotherapy group intervention.

Tailoring Polaron Dimensions in Lead-Tin Hybrid Perovskites.

Charge carriers in the soft and polar perovskite lattice form so-called polaron quasiparticles, charge carriers dressed with a lattice deformation. The spatial extent of a polaron is governed by the material's electron-phonon interaction strength, which determines charge carrier effective mass, mobility, and the so-called Mott polaron density, that is, the maximum stable density of charge carriers that a perovskite can support. Despite its significance, controlling polaron dimensions has been challenging.

Compositional engineering of interfacial charge transfer in van der Waals heterostructures of graphene and transition metal dichalcogenides.

Owing to their unique optical and electronic properties, vertical van der Waals heterostructures (vdWHs) have attracted considerable attention in optoelectronic applications, such as photodetection, light harvesting, and light-emitting diodes. To fully harness these properties, it is crucial to understand the interfacial charge transfer (CT) and recombination dynamics across vdWHs. However, the effects of interfacial energetics and defect states on interfacial CT and recombination processes in graphene-transition metal dichalcogenide (Gr-TMD) vdWHs remain debated.

Self-Blinking Thioflavin T for Super-resolution Imaging.

Thioflavin T (ThT) is a typical dye used to visualize the aggregation and formation of fibrillar structures, e.g., amyloid fibrils and peptide nanofibrils.

Single-Atom Catalysts through Pressure-Controlled Metal Diffusion.

Single-atom catalysts (SACs) open up new possibilities for advanced technologies. However, a major complication in preparing high-density single-atom sites is the aggregation of single atoms into clusters. This complication stems from the delicate balance between the diffusion and stabilization of metal atoms during pyrolysis.

Anisotropic Electron-Phonon Interactions in 2D Lead-Halide Perovskites.

Two-dimensional (2D) hybrid organic-inorganic metal halide perovskites offer enhanced stability for perovskite-based applications. Their crystal structure's soft and ionic nature gives rise to strong interaction between charge carriers and ionic rearrangements. Here, we investigate the interaction of photogenerated electrons and ionic polarizations in single-crystal 2D perovskite butylammonium lead iodide (BAPI), varying the inorganic lamellae thickness in the 2D single crystals.

Odd-Even Alkyl Chain Effects on the Structure and Charge Carrier Transport of Two-Dimensional Sn-Based Perovskite Semiconductors.

Oscillations in the chemical or physical properties of materials, composed of an odd or even number of connected repeating methylene units, are a well-known phenomenon in organic chemistry and materials science. So far, such behavior has not been reported for the important class of materials, perovskite semiconductors. This work reports a distinct odd-even oscillation of the molecular structure and charge carrier transport properties of phenylalkylammonium two-dimensional (2D) Sn-based perovskites in which the alkyl chains in the phenylalkylammonium cations contain varying odd and even carbon numbers.

MXenes with ordered triatomic-layer borate polyanion terminations.

Surface terminations profoundly influence the intrinsic properties of MXenes, but existing terminations are limited to monoatomic layers or simple groups, showing disordered arrangements and inferior stability. Here we present the synthesis of MXenes with triatomic-layer borate polyanion terminations (OBO terminations) through a flux-assisted eutectic molten etching approach. During the synthesis, Lewis acidic salts act as the etching agent to obtain the MXene backbone, while borax generates BO species, which cap the MXene surface with an O-B-O configuration.

Quasi-Homogeneous Photocatalysis in Ultrastiff Microporous Polymer Aerogels.

The development of efficient and low-cost catalysts is essential for photocatalysis; however, the intrinsically low photocatalytic efficiency as well as the difficulty in using and recycling photocatalysts in powder morphology greatly limit their practical performance. Herein, we describe quasi-homogeneous photocatalysis to overcome these two limitations by constructing ultrastiff, hierarchically porous, and photoactive aerogels of conjugated microporous polymers (CMPs). The CMP aerogels exhibit low density but high stiffness beyond 10 m s, outperforming most low-density materials.