The effect of particle size on structural and catalysts for oxygen evolution reaction of (CoFeNiMnCr)O prepared by controlled synthesis with polyvinylpyrrolidone (PVP).

In this study, high-entropy spinel oxides (CoNiMnFeCr)O were synthesized using a PVP-assisted sol-gel method, marking the first report of this approach for producing high-entropy oxides. This method provides new insights into morphology customization through precise temperature control during calcination. Samples were calcined at 800, 900, and 1000 °C, and structural, optical, and electrochemical characterizations were performed to evaluate the impact of synthesis conditions on the oxygen evolution reaction (OER) performance.

Enhancing oxygen reaction kinetics in lanthanum nickelate Ruddlesden-Popper electrodes praseodymium oxide infiltration for solid oxide cells.

This study explores the effect of praseodymium oxide (PrO) impregnation in lanthanum nickelate Ruddlesden-Popper (RP) type materials for use in oxygen electrodes of solid oxide cells (SOCs). These mixed conductors are free of cobalt and strontium, which are increasingly being avoided in solid oxide cell applications. We investigate two compositions, LaNiO (L2N1) and LaNiO (L4N3), demonstrating distinct electrical and oxygen kinetic properties.

Transformation of Metallic Ti to TiH Phase in the Ti/MgH Composite and Its Influence on the Hydrogen Storage Behavior of MgH.

The current work explores the in-situ formation of TiH additive in a Ti/MgH nanocomposite system. Mild mechanical milling leaves Ti chemically unchanged, while formation of stable TiH occurs upon strong mechanical milling. TiH further transforms to TiH upon recycling the powder (dehydrogenation and subsequent hydrogenation) and lowers the activation energy of MgH to 89.

Structure and Electrical-Transport Relations in Ba(Zr,Pr)O Perovskites.

Members of the perovskite solid solution BaZrPrO (0.2 ≤ x ≤ 0.8) with potential high-temperature electrochemical applications were synthesized via mechanical activation and high-temperature annealing at 1250 °C.

Exploring the Thermoelectric Performance of BaGdNiO Haldane Gap Materials.

One-dimensional Haldane gap materials, such as the rare earth barium chain nickelates, have received great interest due to their vibrant one-dimensional spin antiferromagnetic character and unique structure. Herein we report how these 1D structural features can also be highly beneficial for thermoelectric applications by analysis of the system CaBaGdNiO 0 ≤ x ≤ 0.25.

Dehydrogenation Properties of Magnesium Hydride Loaded with Fe, Fe-C, and Fe-Mg Additives.

This study highlights that Fe additives offer better catalytic properties than carbon, Fe-C (iron carbide/carbon composites), and Fe-Mg (Mg FeH ) additives for the low-temperature dehydrogenation of magnesium hydride. The in situ X-ray diffraction measurements prove the formation of a Mg FeH phase in iron additive loaded MgH . Nonetheless, differential scanning calorimetry data suggest that this Mg FeH phase does not have any influence on dehydrogenation properties of MgH .

Site Redistribution, Partial Frozen-in Defect Chemistry, and Electrical Properties of Ba1-x(Zr,Pr)O3-δ.

Changes in nominal composition of the perovskite (ABO3) solid solution Ba1-x(Zr,Pr)O3-δ and adjusted firing conditions at very high temperatures were used to induce structural changes involving site redistribution and frozen-in point defects, as revealed by Raman and photoluminescence spectroscopies. Complementary magnetic measurements allowed quantification of the reduced content of Pr. Weak dependence of oxygen stoichiometry with temperature was obtained by coulometric titration at temperatures below 1000 °C, consistent with a somewhat complex partial frozen-in defect chemistry.

Formation of Mgx Nby Ox+y through the Mechanochemical Reaction of MgH2 and Nb2O5, and Its Effect on the Hydrogen-Storage Behavior of MgH2.

The present study aims to understand the catalysis of the MgH2 -Nb2 O5 hydrogen storage system. To clarify the chemical interaction between MgH2 and Nb2 O5 , the mechanochemical reaction products of a composite mixture of MgH2 +0.167 Nb2 O5 was monitored at different time intervals (2, 5, 15, 30, and 45 min, as well as 1, 2, 5, 10, 15, 20, 25, and 30 h).

Enhancing electrochemical performance by control of transport properties in buffer layers--solid oxide fuel/electrolyser cells.

The current work demonstrates how tailoring the transport properties of thin ceria-based buffer layers in solid oxide fuel or electrolyser cells can provide the necessary phase stability against chemical interaction at the electrolyte/electrode interface, while also providing radical improvements in the electrochemical performance of the oxygen electrode. Half cells of Ce0.8R0.

Temperature dependence of the Henry's law constant for hydrogen storage in NaA zeolites: a Monte Carlo simulation study.

Grand canonical Monte Carlo simulations of hydrogen adsorption in zeolites NaA were carried out for a wide range of temperatures between 77 and 300 K and pressures up to 180 MPa. A potential model was used that comprised of three main interactions: van der Waals, coulombic and induced polarization by the electric field in the system. The computed average number of adsorbed molecules per unit cell was compared with available results and found to be in agreement in the regime of moderate to high pressures.