Elucidating the Complex Oxidation Behavior of Aqueous HPO on Pt Electrodes via Tender X-ray Absorption Near-Edge Structure Spectroscopy at the P -Edge.

tender X-ray absorption near-edge structure (XANES) spectroscopy at the P -edge was utilized to investigate the oxidation mechanism of aqueous HPO on Pt electrodes under various conditions relevant to high-temperature polymer electrolyte membrane fuel cell (HT-PEMFC) applications. XANES and electrochemical analysis were conducted under different tender X-ray irradiation doses, revealing that intense radiation induces the oxidation of aqueous HPO via HO yielding HPO and H. A broadly applicable experimental procedure was successfully developed to suppress these undesirable radiation-induced effects, enabling a more accurate determination of the aqueous HPO oxidation mechanism.

Oxidation of Aqueous Phosphorous Acid Electrolyte in Contact with Pt Studied by X-ray Photoemission Spectroscopy.

The oxidation of the aqueous HPO in contact with Pt was investigated for a fundamental understanding of the Pt/aqueous HPO interaction with the goal of providing a comprehensive basis for the further optimization of high-temperature polymer electrolyte membrane fuel cells (HT-PEMFCs). Ion-exchange chromatography (IEC) experiments suggested that in ambient conditions, Pt catalyzes HPO oxidation to HPO with HO. X-ray photoelectron spectroscopy (XPS) on different substrates, including Au and Pt, previously treated in HPO solutions was conducted to determine the catalytic abilities of selected metals toward HPO oxidation.

Dual Oxygen Defects in Layered LaSrBaInO (x = 0.2, 0.3) Oxide-Ion Conductors: A Neutron Diffraction Study.

The title compounds exhibit a KNiF-type layered perovskite structure; they are based on the LaSrInO oxide, which was found to exhibit excellent features as fast oxide-ion conductor via an interstitial oxygen mechanism. These new Ba-containing materials were designed to present a more open framework to enhance oxygen conduction. The citrate-nitrate soft-chemistry technique was used to synthesize such structural perovskite-type materials, followed by annealing in air at moderate temperatures (1150 °C).

Electrochemical adsorption of OH on Pt(111) in alkaline solutions: combining DFT and molecular dynamics.

The adsorption of OH on Pt(111) in alkaline solution has been investigated by a method that combines density functional theory, molecular dynamics, and quantum statistical mechanics. In particular, we have calculated the free energy surface for the reaction. A physisorbed hydroxide ion in a metastable state and a stable adsorbed uncharged OH group are observed.