Iridium-based particles, regarded as the most promising proton exchange membrane electrolyzer electrocatalysts, were investigated by transmission electron microscopy and coupling of an electrochemical flow cell (EFC) with online inductively coupled plasma mass spectrometry. Additionally, studies using a thin-film rotating disc electrode, identical location scanning microscopy, well X-ray absorption spectroscopy have been performed. Extremely sensitive time-and potential-resolved dissolution...

To increase the power density of battery materials, without significantly affecting their main advantage a high energy density, novel material architectures need to be developed. Using example LiFePO4, we demonstrate simple, sol−gel-based route that leads large (up 20 μm) primary LiFePO4 particles, each which contains hierarchically organized pores in meso and macro range. As are formed due vigorous gas evolution (mainly CO CO2) during degradation citrate precursor, they perfectly...

Abstract Wet hydrogen peroxide catalytic oxidation (WHPCO) is one of the most important industrially applicable advanced processes (AOPs) for decomposition organic pollutants in water. It demonstrated that manganese functionalized silicate nanoparticles with interparticle porosity act as a superior Fenton‐type nanocatalyst WHPCO they can decompose 80% test compound 30 minutes at neutral pH and room temperature. By using X‐ray absorption spectroscopic techniques it also shown activity be...

Understanding the mechanism(s) of polysulfide formation and knowledge about interactions sulfur polysulfides with a host matrix electrolyte are essential for development long-cycle-life lithium-sulfur (Li-S) batteries. To achieve this goal, new analytical tools need to be developed. Herein, K-edge X-ray absorption near-edge structure (XANES) (6,7) Li magic-angle spinning (MAS) NMR studies on Li-S battery its components reported. The characterization different stoichiometric mixtures lithium...

Magnesium–sulfur batteries are considered as attractive energy-storage devices due to the abundance of electrochemically active materials and high theoretical energy density. Here we report mechanism a Mg–S battery operation, which was studied in presence simple commercially available salts dissolved mixture glymes. The electrolyte offers sulfur conversion into MgS first discharge with low polarization. electrochemical magnesium proceeds through two well-defined plateaus, correspond...

Combining the abundance and inexpensiveness of their constituent elements with atomic dispersion, atomically dispersed Fe-N-C catalysts represent most promising alternative to precious-metal-based materials in proton exchange membrane (PEM) fuel cells. Due high temperatures involved synthesis sensitivity Fe ions toward carbothermal reduction, current synthetic methods are intrinsically limited type amount desired, catalytically active Fe-N4 sites, site densities have been out reach (dilemma...

X-ray absorption spectroscopy is a synchrotron radiation based technique that able to provide information on both local structure and electronic properties in chemically selective manner. It can be used characterize the dynamic processes govern electrochemical energy storage batteries, shed light redox chemistry changes during galvanostatic cycling design cathode materials with improved properties. Operando XAS studies have been performed at beamline XAFS Elettra different systems. For...

Dry reforming of methane (DRM) is a promising way to convert and carbon dioxide into H2 CO (syngas). CeO2 nanorods, nanocubes, nanospheres were decorated with 1-4 wt % Ni. The materials structurally characterized using TEM in situ XANES/EXAFS. CO2 activation was analyzed by DFT temperature-programmed techniques combined MS-DRIFTS. Synthesized morphologies expose {111} {100} terminating facets, varying the strength interaction redox properties, which influence activation....

The microalgae Spirulina may be a popular dietary supplement rich in essential nutrients and vitamins, but oversight of the industry, general, remains limited, increasing incidents adulteration, misbranding, undeclared ingredients together with misleading claims create potential risks. In response, this study characterized elemental, amino acid fatty content commercially available supplements Slovenia using EDXRF, ICP-MS GC-MS compared results their nutritional declaration. gathered data...

Calcium chromates with the empirical formulas Ca 10 Cr 6 −O 25 , 3 2 O 8 and 5 12 which form at temperatures >900°C CaO:Cr molar ratios of in an oxidation atmosphere have been synthesized pure state. X‐ray absorption near‐edge structure (XANES) spectroscopy has used to determine average valence state chromium samples. The presence unusual states, 4+ 5+, was proposed via diffractometry studies, is strongly supported.

By employing new electrolytes, the polysulfide shuttle phenomenon, one of main problems lithium–sulfur (Li–S) batteries, can be significantly reduced. Here we present excellent Coulombic efficiencies as well adequate performance high-energy Li–S cells by use a fluorinated ether (TFEE) based electrolyte at low loading. The observed altered discharge profile was investigated both electrochemical experiments and an especially tailored COSMO-RS computational approach, while details mechanism...

Cadmium and zinc share many similar physiochemical properties, but their compartmentation, complexation impact on other mineral element distribution in plant tissues may drastically differ. In this study, we address the of 10 μm Cd or 50 Zn treatments ion leaves a metallicolous population non-hyperaccumulating species Zygophyllum fabago at tissue cell level, consequences response through combined physiological, proteomic metabolite approach. Micro-proton-induced X-ray emission laser ablation...

The positive effect of intermetallic ordering platinum alloy nanoparticles on oxygen reduction reaction (ORR) activity has been well established. What is still missing an understanding selective leaching the less noble metal from ordered structure and its correlation to long-term ORR performance. Using a combination kinetic Monte Carlo simulations advanced characterization techniques, we provide unprecedented insight into dealloying PtCu3 nanoparticles—a well-known binary alloy. Comparison...

A mechanism for Li–S battery operation with a composite electrode and an adsorption additive obtained by using operando ultraviolet/visible (UV/vis) spectroscopy X-ray absorption confirms the role of reflects conversion sulfur into Li2S. Operando UV/vis shows reversible appearance long-chain polysulfides in separator fifth cycle, whereas mid- short-chain suggests polysulfide shuttle mechanism. By nonsulfur-containing electrolyte, high-precision analysis K-edge near-edge (XANES) extended fine...

The high structural and compositional flexibility of metal–organic frameworks (MOFs) shows their great potential for CO2 capture utilization in accordance with the environmental guidelines low-carbon technology developments. HKUST-1 as one most intensively studied representatives MOFs such purposes excels because its simplicity production ability to tune intrinsic properties by various functionalization processes. In present work, ethylenediamine was performed first time order thoroughly...

The development of affordable, low-iridium-loading, scalable, active, and stable catalysts for the oxygen-evolution reaction (OER) is a requirement commercialization proton-exchange membrane water electrolyzers (PEMWEs). However, synthesis high-performance OER with minimal use rare expensive element Ir very challenging requires identification electrically conductive high-surface-area support materials. We developed procedure production large quantities nanocomposite powder containing...

Technologies for mass production require cheap and abundant materials such as ferrous chloride (FeCl

A series of iron-containing mesoporous silicas (Fe-HMS) with Fe contents up to 5.7 wt.% have been prepared at room temperature using the neutral hexadecylamine as surfactant molecule. Characterization these materials by a variety spectroscopic techniques, including EXAFS, EPR, Mössbauer and UV–Vis spectroscopies, suggests that species are tetrahedrally coordinated in as-made materials. Tetrahedra highly distorted two long short Fe–O bond distances due hydrogen-bonding type interactions...

Solid solutions between iron and manganese cations in were successfully prepared by hydrothermal synthesis. The selected sample was electrochemically evaluated the use of two situ characterization techniques. Although showed good reversibility with a large voltage polarization formation cycles, observed electrochemical activity is only partly connected change oxidation states and/or manganese. Using techniques (Mössbauer spectroscopy X-ray absorption near-edge structure), most reversibly...