Chemical Interactions at the Interface of Au on BiSe Topological Insulator.

This study explores the intricate chemical processes at the interface between the topological insulator BiSe and deposited Au. The study mainly focused on room-temperature interactions that can cause the aging of, e.g.

Understanding the in-situ transformation of CuO interlayers to increase the water splitting efficiency in NiO/n-Si photoanodes.

The buried interface tens of nanometers beneath the solid-liquid junction is crucial for photocarrier extraction, influencing the overall efficiency of photoelectrochemical devices. Precise characterization of the interfacial properties is essential for device optimization but remains challenging. Here, we directly probe the in situ transformation of a CuO interlayer at the NiO/n-Si interface by hard X-ray photoelectron spectroscopy.

Back to the future with emerging iron technologies.

Here is a comprehensive overview of iron's potential in low-carbon energy technologies, exploring applications like metal fuel combustion, iron-based batteries, and energy-carrier cycles, as well as sustainable approaches for production and recycling with a focus on reducing environmental impact. Iron, with its abundance, safety, and electrochemical characteristics, is a promising material to contribute to a decarbonized future. This paper discusses the advancements and challenges in iron-based energy storage technologies and sustainable iron production methods.

Designing Atomic Interface in SbS/CdS Heterojunction for Efficient Solar Water Splitting.

In the emerging SbS-based solar energy conversion devices, a CdS buffer layer prepared by chemical bath deposition is commonly used to improve the separation of photogenerated electron-hole pairs. However, the cation diffusion at the SbS/CdS interface induces detrimental defects but is often overlooked. Designing a stable interface in the SbS/CdS heterojunction is essential to achieve high solar energy conversion efficiency.

The Role of Lattice Defects on the Optical Properties of TiO Nanotube Arrays for Synergistic Water Splitting.

In this study, we report a facile one-step chemical method to synthesize reduced titanium dioxide (TiO) nanotube arrays (NTAs) with point defects. Treatment with NaBH introduces oxygen vacancies (OVs) in the TiO lattice. Chemical analysis and optical studies indicate that the OV density can be significantly increased by changing reduction time treatment, leading to higher optical transmission of the TiO NTAs and retarded carrier recombination in the photoelectrochemical process.

Self-adaptive amorphous CoOCl electrocatalyst for sustainable chlorine evolution in acidic brine.

Electrochemical chlorine evolution reaction is of central importance in the chlor-alkali industry, but the chlorine evolution anode is largely limited by water oxidation side reaction and corrosion-induced performance decay in strong acids. Here we present an amorphous CoOCl catalyst that has been deposited in situ in an acidic saline electrolyte containing Co and Cl ions to adapt to the given electrochemical condition and exhibits ~100% chlorine evolution selectivity with an overpotential of ~0.1 V at 10 mA cm and high stability over 500 h.

Nitroreductase-sensitive fluorescent covalent organic framework for tumor hypoxia imaging in cells.

Covalent organic frameworks (COFs) have been used in cell imaging, but very rarely for imaging specific cell conditions. Herein, a β-ketoenamine-based fluorescent COF was post-synthetically modified to incorporate a hypoxia-targeting molecule. Fluorescence microscopy imaging shows that the material discriminates between HeLa cells grown under hypoxia and those cultured under normoxia.

Silica Coated BiSe Topological Insulator Nanoparticles: An Alternative Route to Retain Their Optical Properties and Make Them Biocompatible.

Localized surface plasmon resonance (LSPR) is the cause of the photo-thermal effect observed in topological insulator (TI) bismuth selenide (BiSe) nanoparticles. These plasmonic properties, which are thought to be caused by its particular topological surface state (TSS), make the material interesting for application in the field of medical diagnosis and therapy. However, to be applied, the nanoparticles have to be coated with a protective surface layer, which prevents agglomeration and dissolution in the physiological medium.

Non-covalent ligand-oxide interaction promotes oxygen evolution.

Strategies to generate high-valence metal species capable of oxidizing water often employ composition and coordination tuning of oxide-based catalysts, where strong covalent interactions with metal sites are crucial. However, it remains unexplored whether a relatively weak "non-bonding" interaction between ligands and oxides can mediate the electronic states of metal sites in oxides. Here we present an unusual non-covalent phenanthroline-CoO interaction that substantially elevates the population of Co sites for improved water oxidation.

Saturation magnetisation as an indicator of the disintegration of barium hexaferrite nanoplatelets during the surface functionalisation.

Barium hexaferrite nanoplatelets (BHF NPLs) are permanent nanomagnets with the magnetic easy axis aligned perpendicular to their basal plane. By combining this specific property with optimised surface chemistry, novel functional materials were developed, e.g.

Cationic Covalent Organic Polymer Thin Film for Label-free Electrochemical Bacterial Cell Detection.

Numerous species of bacteria pose a serious threat to human health and cause several million deaths annually. It is therefore essential to have quick, efficient, and easily operable methods of bacterial cell detection. Herein, we synthesize a novel cationic covalent organic polymer (COP) named through the Menshutkin reaction and evaluate its potential as an impedance sensor for cells.

Structure and Population of Complex Ionic Species in FeCl Aqueous Solution by X-ray Absorption Spectroscopy.

Technologies for mass production require cheap and abundant materials such as ferrous chloride (FeCl). The literature survey shows the lack of experimental studies to validate theoretical conclusions related to the population of ionic Fe-species in the aqueous FeCl solution. Here, we present an in situ X-ray absorption study of the structure of the ionic species in the FeCl aqueous solution at different concentrations (1-4 molL) and temperatures (25-80 °C).

Enhancing the Mechanical Properties of Biodegradable Mg Alloys Processed by Warm HPT and Thermal Treatments.

In this study, several biodegradable Mg alloys (Mg5Zn, Mg5Zn0.3Ca, Mg5Zn0.15Ca, and Mg5Zn0.

Implicit water model within the Zimm-Bragg approach to analyze experimental data for heat and cold denaturation of proteins.

Studies of biopolymer conformations essentially rely on theoretical models that are routinely used to process and analyze experimental data. While modern experiments allow study of single molecules in vivo, corresponding theories date back to the early 1950s and require an essential update to include the recent significant progress in the description of water. The Hamiltonian formulation of the Zimm-Bragg model we propose includes a simplified, yet explicit model of water-polypeptide interactions that transforms into the equivalent implicit description after performing the summation of solvent degrees of freedom in the partition function.

Covalent Organic Polymers and Frameworks for Fluorescence-Based Sensors.

Following the advancements and diversification in synthetic strategies for porous covalent materials in the literature, the materials science community started to investigate the performance of covalent organic polymers (COPs) and covalent organic frameworks (COFs) in applications that require large surface areas for interaction with other molecules, chemical stability, and insolubility. Sensorics is an area where COPs and COFs have demonstrated immense potential and achieved high levels of sensitivity and selectivity on account of their tunable structures. In this review, we focus on those covalent polymeric systems that use fluorescence spectroscopy as a method of detection.

The Finite Size Effects and Two-State Paradigm of Protein Folding.

The coil to globule transition of the polypeptide chain is the physical phenomenon behind the folding of globular proteins. Globular proteins with a single domain usually consist of about 30 to 100 amino acid residues, and this finite size extends the transition interval of the coil-globule phase transition. Based on the pedantic derivation of the two-state model, we introduce the number of amino acid residues of a polypeptide chain as a parameter in the expressions for two cooperativity measures and reveal their physical significance.

Oxygen Vacancy-Related Cathodoluminescence Quenching and Polarons in CeO.

We used cathodoluminescence (CL) spectroscopy to characterize the oxygen vacancies (V) in ceria (CeO). The effects of the processing atmosphere and thermal quenching temperature on the nature and distribution of the intrinsic defects and on the spectroscopic behavior were investigated. The presence of polarons and associates of the polarons with the oxygen vacancies such as (V -Ce ) is demonstrated.

Formation of Fe(III)-phosphonate Coatings on Barium Hexaferrite Nanoplatelets for Porous Nanomagnets.

Amorphous coatings formed with mono-, di-, and tetra-phosphonic acids on barium hexaferrite (BHF) nanoplatelets using various synthesis conditions. The coatings, synthesized in water with di- or tetra-phosphonic acids, were thicker than that could be expected from the ligand size and the surface coverage, as determined by thermogravimetric analysis. Here, we propose a mechanism for coating formation based on direct evidence of the surface dissolution/precipitation of the BHF nanoplatelets.

Inherent Surface Properties of Adsorbent-Free Ultrathin BiSe Topological Insulator Platelets.

We report on a hydrothermal synthesis of hexagonal ultra-thin BiSe platelets, which was performed without any organic reactants. The synthesis resulted in the particles with a surface, clean of any organic adsorbents, which was confirmed with a high-resolution transmission electron microscopy, zeta-potential measurements and thermogravimetric measurements coupled with a mass spectroscopy. Due to the absence of the adsorbed organic layer on the BiSe platelet surface, we were able to measure their inherent surface and optical properties.

A DNA origami plasmonic sensor with environment-independent read-out.

DNA origami is a promising technology for its reproducibility, flexibility, scalability and biocompatibility. Among the several potential applications, DNA origami has been proposed as a tool for drug delivery and as a contrast agent, since a conformational change upon specific target interaction may be used to release a drug or produce a physical signal, respectively. However, its conformation should be robust with respect to the properties of the medium in which either the recognition or the read-out take place, such as pressure, viscosity and any other unspecific interaction other than the desired target recognition.

Plasma-Induced Crystallization of TiO₂ Nanotubes.

Facile crystallization of titanium oxide (TiO₂) nanotubes (NTs), synthesized by electrochemical anodization, with low pressure non-thermal oxygen plasma is reported. The influence of plasma processing conditions on TiO₂ NTs crystal structure and morphology was examined by X-ray diffraction (XRD) and scanning electron microscopy (SEM). For the first time we report the transition of amorphous TiO₂ NTs to anatase and rutile crystal structures upon treatment with highly reactive oxygen plasma.

Study of silica-based intrinsically emitting nanoparticles produced by an excimer laser.

We report an experimental study demonstrating the feasibility to produce both pure and Ge-doped silica nanoparticles (size ranging from tens up to hundreds of nanometers) using nanosecond pulsed KrF laser ablation of bulk glass. In particular, pure silica nanoparticles were produced using a laser pulse energy of 400 mJ on pure silica, whereas Ge-doped nanoparticles were obtained using 33 and 165 mJ per pulse on germanosilicate glass. The difference in the required energy is attributed to the Ge doping, which modifies the optical properties of the silica by facilitating energy absorption processes such as multiphoton absorption or by introducing absorbing point defects.

Polymer nanoparticle sizes from dynamic light scattering and size exclusion chromatography: the case study of polysilanes.

Dynamic light scattering (DLS) and size exclusion chromatography (SEC) are among the most popular methods for determining polymer sizes in solution. Taking dendritic and network polysilanes as a group of least soluble polymer substances, we critically compare and discuss the difference between nanoparticle sizes, obtained by DLS and SEC. Polymer nanoparticles are typically in poor solution conditions below the theta point and are therefore in the globular conformation.

Room-Temperature Synthesis and Optical Properties of NdVO4 Nanoneedles.

Tetragonal NdVO4 nanoneedles were prepared via a simple room-temperature precipitation method in the absence of any surfactant or template, starting from simple inorganic salts, NdCl3 and Na3VO4, as raw materials. The nanoneedles were characterized by XRPD, SEM, Raman, PL, and lifetime spectroscopy. The particles have a length of about 100 nm and a diameter of 20 nm and grow along <112> direction.

TiO-SnS nanocomposites: solar-active photocatalytic materials for water treatment.

The study is aimed at evaluating TiO-SnS composites as effective solar-active photocatalysts for water treatment. Two strategies for the preparation of TiO-SnS composites were examined: (i) in-situ chemical synthesis followed by immobilization on glass plates and (ii) binding of two components (TiO and SnS) within the immobilization step. The as-prepared TiO-SnS composites and their sole components (TiO or SnS) were inspected for composition, crystallinity, and morphology using Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), X-ray diffraction (XRD), and scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM/EDX) analyses.