Synthesis of Pd-Pt Ultrathin Assembled Nanosheets as Highly Efficient Electrocatalysts for Ethanol Oxidation

The excellent performance of oxygen evolution reaction on stainless steel electrodes by halogen oxyacid salts etching

Development of low-cost, efficient, and stable electrocatalysts for oxygen evolution reaction (OER) is the key issue for a large-scale hydrogen production. Recently, in-situ corrosion of stainless steel seems to be a feasible technique to obtain an efficient OER electrode, while a wide variety of corrosive agents often lead to significant difference in catalytic performance. Herein, we synthesized Ni-Fe based nanomaterials with OER activity through a facile one-step hydrothermal etching method of stainless steel mesh, and investigated the influence of three halogen oxyacid salts (KClO3, KBrO3, KIO3) on water oxidation performance. It was found that the reduction product of oxyacid salts has the pitting effect on the stainless steel, which plays an important role in regulating the morphology and composition of the nanomaterials. The KBrO3-derived electrode shows optimal OER performance, giving the small overpotential of 228 and 270 mV at 10 and 100 mA cm-2 respectively, a low Tafel slope of 36.2 mV dec-1, as well as durable stability in the long-time electrolysis. This work builds an internal relationship between the corrosive agents and the OER performance of the as-prepared electrodes, providing promising strategies and research foundations for further improving the OER performance and optimizing the structure of stainless steel electrodes.

In situ surface analysis of palladium-platinum alloys in methane oxidation conditions

Palladium and palladium-platinum foils were analysed using temperature-programmed near-ambient pressure X-ray photoelectron spectroscopy (TP-NAP-XPS) under methane oxidation conditions. Oxidation of palladium is inhibited by the presence of water, and in oxygen-poor environments. Pt addition further inhibits oxidation of palladium across all reaction conditions, preserving metallic palladium to higher temperatures. Bimetallic foils underwent significant restructuring under reaction conditions, with platinum preferentially migrating to the bulk under select conditions.

Highly Porous Au-Pt Bimetallic Urchin-Like Nanocrystals for Efficient Electrochemical Methanol Oxidation

Highly porous Au–Pt urchin-like bimetallic nanocrystals have been prepared by a one-pot wet-chemical synthesis method. The porosity of urchin-like bimetallic nanocrystals was controlled by amounts of hydrazine used as reductant. The prepared highly porous Au-Pt urchin-like nanocrystals were superior catalysts of electrochemical methanol oxidation due to high porosity and surface active sites by their unique morphology. This approach will pave the way for the design of bimetallic porous materials with unprecedented functions.