High-Performance Anion Exchange Membrane Water Electrolyzers Enabled by Highly Gas Permeable and Dimensionally Stable Anion Exchange Ionomers.

Designing suitable anion exchange ionomers is critical to improving the performance and in situ durability of anion exchange membrane water electrolyzers (AEMWEs) as one of the promising devices for producing green hydrogen. Herein, highly gas-permeable and dimensionally stable anion exchange ionomers (QC6xBA and QC6xPA) are developed, in which bulky cyclohexyl (C6) groups are introduced into the polymer backbones. QC6BA-2.

NiFe Alloy Integrated with Amorphous/Crystalline NiFe Oxide as an Electrocatalyst for Alkaline Hydrogen and Oxygen Evolution Reactions.

The rational design of efficient and low-cost electrocatalysts based on earth-abundant materials is imperative for large-scale production of hydrogen by water electrolysis. Here we present a strategy to prepare highly active catalyst materials through modifying the crystallinity of the surface/interface of strongly coupled transition metal-metal oxides. We have thermally activated the catalysts to construct amorphous/crystalline Ni-Fe oxide interfaced with a conductive Ni-Fe alloy and systematically investigated their electrocatalytic performance toward the hydrogen evolution and oxygen evolution reactions (HER and OER) in alkaline solution.

Electronic States and Transport Phenomena of Pt Nanoparticle Catalysts Supported on Nb-Doped SnO for Polymer Electrolyte Fuel Cells.

Semiconducting oxide nanoparticles are strongly influenced by surface-adsorbed molecules and tend to generate an insulating depletion layer. The interface between a noble metal and a semiconducting oxide constructs a Schottky barrier, interrupting the electron transport. In the case of a Pt catalyst supported on the semiconducting oxide Nb-doped SnO with a fused-aggregate network structure (Pt/Nb-SnO) for polymer electrolyte fuel cells, the electronic conductivity increased abruptly with increasing Pt loading, going from 10 to 10 S cm.

Electrochemical oxidation of hydrolyzed poly oxymethylene-dimethyl ether by PtRu catalysts on Nb-doped SnO(2-δ) supports for direct oxidation fuel cells.

We synthesized Pt and PtRu catalysts supported on Nb-doped SnO(2-δ) (Pt/Sn0.99Nb0.01O(2-δ), PtRu/Sn0.

Temperature- and humidity-controlled SAXS analysis of proton-conductive ionomer membranes for fuel cells.

We report herein temperature- and humidity-controlled small-angle X-ray scattering (SAXS) analyses of proton-conductive ionomer membranes. The morphological changes of perfluorosulfonic acid polymers (Nafion and Aquivion) and sulfonated aromatic block copolymers (SPE-bl-1 and SPK-bl-1) were investigated and compared under conditions relevant to fuel cell operation. For the perfluorinated ionomer membranes, water molecules were preferentially incorporated into ionic clusters, resulting in phase separation and formation of ion channels.

Temperature dependence of oxygen reduction reaction activity at stabilized Pt skin-PtCo alloy/graphitized carbon black catalysts prepared by a modified nanocapsule method.

We have developed a new catalyst supported on graphitized carbon black (GCB), which exhibits higher resistance to carbon corrosion than a conventional carbon black (CB), in order to favor both high mass activity for the oxygen reduction reaction (ORR) and high durability. To protect the underlying Pt(X)Co alloy from corrosion and maintain the modified electronic structure, two monolayers of Pt-skin layer (Pt(2 ML)) were formed on the Pt(X)Co core-particles, which were of uniform size and composition. Characterization of the Pt(2 ML)-PtCo(X = 1)/GCB, both by a scanning transmission electron microscope (STEM) with an energy dispersive X-ray (EDX) analyzer and by X-ray diffraction (XRD), indicated the formation of the Pt(2 ML) on the PtCo alloy solid solution nanoparticles.