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The alkali metal-induced deactivation of a novel CeO(2)-WO(3) (CeW) catalyst used for selective catalytic reduction (SCR) was investigated. The CeW catalyst could resist greater amounts of alkali metals than V(2)O(5)-WO(3)/TiO(2). At the same molar concentration, the K-poisoned catalyst exhibited a greater loss in activity compared with the Na-poisoned catalyst below 200 °C. A combination of experimental and theoretical methods, including NH(3)-TPD, DRIFTS, H(2)-TPR, and density functional theory (DFT) calculations, were used to elucidate the mechanism of the alkali metal deactivation of the CeW catalyst in SCR reaction. Experiments results indicated that decreases in the reduction activity and the quantity of Brønsted acid sites rather than the acid strength were responsible for the catalyst deactivation. The DFT calculations revealed that Na and K could easily adsorb on the CeW (110) surface and that the surface oxygen could migrate to cover the active tungsten, and then inhibit the SCR of NO(x) with ammonia. Hot water washing is a convenient and effective method to regenerate alkali metal-poisoned CeW catalysts, and the catalytic activity could be recovered 90% of the fresh catalyst.

Highlights A new class of TiO2 nanofiber/red phosphorus (TiO2/RP) nanolayer core/shell heterostructure was fabricated by vaporization-deposition strategy. TiO2/RP exhibits enhanced photocatalytic pure water splitting performance. Decoration of RP extends the optical light harvesting ability.  P 5+ doping induced oxygen vacancies improve the charge separation efficiency.

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Magnesium-lithium base alloy is one of the lightest metallic engineering materials with a density of 1?35-1?65 g cm 23 , which is referred to as superlight materials. It has become an attractive material in the fields of aerospace, automobiles, portable electronics, etc. In this paper, the developing history and recent progress of superlight magnesium-lithium base alloys are reviewed. The progress on molten electrolysis preparation, processing technologies and surface processing technologies are introduced, and future research directions are suggested based on the current research progress.