The MXenes are a class of 2D materials composed transition-metal sheets alternating with carbide/nitride sheets, stacked just few atoms thick. discovered thus far also have surface termination layer that is likely mixture hydroxides and fluorides. While reasonable structural models based on X-ray diffraction transmission electron microscopy data exist, the exact nature distribution species not well understood. Here, 1H, 19F, 13C solid-state NMR spectroscopies used to investigate model MXene...

The active phase responsible for low-temperature CO oxidation in nanoparticulate CuO/CeO2 catalysts was identified as surface-substituted CuyCe1–yO2–x. Contrary to previous studies, our measurements on a library of well-defined have proven that the CuO is spectator species, whereas CuyCe1–yO2–x oxidation. Using situ X-ray absorption spectroscopy, we found copper ions remain at high states (Cu3+ and Cu2+) under oxygen-rich catalytic conditions without any evidence Cu+. Artificial neural...

The dielectric response of two-dimensional (2D) ${\mathrm{Ti}}_{3}{\mathrm{C}}_{2}$ stacked sheets was investigated by high-resolution transmission electron energy-loss spectroscopy and ab initio calculations in the 0.2--30-eV energy range. Intense surface plasmons (SPs), evidenced at nanometer scale energies as low 0.3 eV, are shown to be dominant screening process up least 45-nm-thick stacks. This domination results from a combination efficient free-electron dynamics, begrenzungs effect,...

A platform for producing stabilized Pt atoms and clusters through the combination of an N-doped graphene support atomic layer deposition (ALD) catalysts was investigated using transmission electron microscopy (TEM) scanning (STEM). It determined, imaging spectroscopy techniques, that a wide range N-dopant types entered lattice covalent bonds without largely damaging its structure. Additionally most notably, formed in absence nanoparticles. This work provides new strategy experimentally...

Despite their highly efficient plasmonic properties, gold nanoparticles are currently preferred to silver for biomedical applications such as photothermal therapy due high chemical stability in the biological environment. To confer protection while preserving we allied advantages of both materials and produced hybrid made an anisotropic nanoplate core coated with a frame gold. The efficiency these (Ag@AuNPs) photothermia was compared monometallic nanoplates (AgNPs) or nanostars (AuNPs)....

We report on the molecular beam epitaxial growth and structural characterization of self-organized AlGaN nanowire arrays Si substrate with high luminescence efficiency emission in deep ultraviolet (UV) wavelength range. It is found that, increasing Al concentration, atomic-scale compositional modulations can be realized, leading to three-dimensional quantum confinement charge carriers. By further exploiting Anderson localization light, we have demonstrated, for first time, electrically...

Pt single atoms, stable on alumina under O₂, form mobile clusters H₂, due to adsorbate- and nuclearity-dependent metal-support interaction.

Fine-tuning nanocatalysts to enhance their catalytic activity and durability is crucial commercialize proton exchange membrane fuel cells. The structural ordering time evolution of ordered Pt3Fe2 intermetallic core–shell for the oxygen reduction reaction that exhibit increased mass (228%) an enhanced (155%) compared Pt/C has been quantified using aberration-corrected scanning transmission electron microscopy. These catalysts were found a static core–dynamic shell regime wherein, despite...

Controlling plasmonic systems with nanometer resolution in transparent films and their colors over large nonplanar areas is a key issue for spreading use various industrial fields. Using light to direct self-organization mechanisms provides high-speed flexible processes meet this challenge. Here, we describe route the laser-induced of metallic nanostructures 3D. Going beyond production planar nanopatterns, demonstrate that ultrafast excitation combined nonlinear feedback nanocomposite thin...

Multifunctional nanoparticles such as magneto‐plasmonic nanohybrids are rising theranostic agents. However, little is yet known of their fate within the cellular environment. In order to reach an understanding biotransformations, reliable metrics for tracking and quantification materials properties during intracellular journey needed. this study, long‐term (one month) followed stem‐cell spheroids used tissue replicas. A set magnetic (magnetization) thermal (magnetic hyperthermia,...

Study on the chemical and structural degradation of layered lithium transition metal oxide cathode material upon electrochemical cycling.

Repeated attacks using organophosphorus compounds, in military conflicts or terrorist acts, necessitate developing inexpensive and readily available decontamination systems. Nanosized cerium oxide is a suitable candidate when presents {111} facets.

Ceria is one of the world's most prominent material for applications in heterogeneous catalysis, as catalyst support or itself. Despite an exhaustive literature on structure reactive facets CeO2 line with its catalytic mechanisms, temporal evolution atomic surface exposed to realistic redox conditions remains elusive. Here, we provide a direct visualization mobility cerium atoms {100} surfaces nanocubes at room temperature high vacuum, O2, and CO2 atmospheres environmental transmission...

We report on the detailed molecular beam epitaxial growth and characterization of Al(Ga)N nanowire heterostructures Si their applications for deep ultraviolet light emitting diodes lasers. The nanowires are formed under nitrogen-rich conditions without using any metal catalyst. Compared to conventional epilayers, Mg-dopant incorporation is significantly enhanced in nearly strain- defect-free structures, leading efficient p-type conduction. resulting LEDs exhibit excellent performance,...

Abstract Hafnium zirconium oxide (HZO) is an ideal candidate for the implementation of ferroelectric memristive devices, due to its compatibility with complementary metal‐oxide‐semiconductor technology. Ferroelectricity in HZO films significantly influenced by properties electrode/HZO interfaces. Here, impact interfacial microstructure and chemistry on ferroelectricity 6 nm‐thick HZO‐based capacitors, realized sputtering, titanium nitride or tungsten electrode materials, investigated. The...

Cr${}_{2}$GeC thin films were grown by magnetron sputtering from elemental targets. Phase-pure was directly onto Al${}_{2}$O${}_{3}$(0001) at temperatures of 700--800 \ifmmode^\circ\else\textdegree\fi{}C. These have an epitaxial component with the well-known relationship Cr${}_{2}$GeC(0001)//Al${}_{2}$O${}_{3}$(0001) and ${\mathrm{Cr}}_{2}\mathrm{GeC}(11\overline{2}0)//{\mathrm{Al}}_{2}{\mathrm{O}}_{3}(1\overline{1}00)$ or...

From x-ray magnetic circular dichroism experiments performed at low temperature on Cr2AlC and Cr2GeC thin films, it is evidenced that Cr atoms carry a net moment in these ternary phases. It shown the magnetization of Al-based compound nearly vanished 100 K agreement with what has been recently observed bulk. X-ray linear measurements various angles incidence temperatures clearly demonstrate existence charge ordering along c axis structure Cr2AlC. All experimental observations support, part,...

Abstract Printed image multiplexing based on the design of metasurfaces has attracted much interest in past decade. Optical switching between different images displayed directly metasurface is performed by altering parameters incident light such as polarization, wavelength, or incidence angle. When using white light, only two‐image implemented with polarization switching. Such are made nanostructures perfectly controlled individually, which provide high‐resolution pixels but small and...

The spatial distributions of antibonding ${\ensuremath{\pi}}^{*}$ and ${\ensuremath{\sigma}}^{*}$ states in epitaxial graphene multilayers are mapped using electron energy-loss spectroscopy a scanning transmission microscope. Inelastic channeling simulations validate the interpretation spatially resolved signals terms electronic orbitals, demonstrate crucial effect material thickness on experimental capability to resolve distribution unoccupied states. This work illustrates current potential...