A new POMOF consisting of [VW 12 ] 4− clusters and metal-organic nanotubes: Synthesis, structure, electrocatalytic and luminescent properties

Design and Synthesis of Amphiphilic Catalyst [C16mim]5VW12O40Br and Its Application in Deep Desulfurization with Superior Cyclability at Room Temperature

Achieving long-term stable deep desulfurization at room temperature and recovering high value-added sulfone products is a challenge at present. Herein, a series of catalysts [C_nmim]₅VW₁₂O₄₀Br (C_nVW₁₂, 1-alkyl-3-methylimidazolium bromide tungstovanadate, n = 4, 8, 16) were presented for the room temperature catalytic oxidation of dibenzothiophene (DBT) and its derivatives. Factors affecting the reaction process, such as the amount of catalyst, oxidant, and temperature, were systematically discussed. C₁₆VW₁₂ showed higher catalytic performance, and 100% conversion and selectivity could be achieved in 50 min with only 10 mg. The mechanism study showed that the hydroxyl radical was the active radical in the reaction. Benefiting from the "polarity strategy", the sulfone product accumulated after 23 cycles in a C₁₆VW₁₂ system, and the yield and purity were about 84% and 100%, respectively.

Tungsten and Molybdenum Heteropolyanions with Different Central Ions—Correlation between Theory and Experiment

Density functional theory calculations were carried out to investigate the electronic structures of Keggin-typed [XMo₁₂O₄₀]ⁿ⁻ and [XW₁₂O₄₀]ⁿ⁻ anions with different heteroatoms (X = Zn²⁺, B³⁺, Al³⁺, Ga³⁺, Si⁴⁺, Ge⁴⁺, P⁵⁺, As⁵⁺, and S⁶⁺). The influence of solvent on redox properties of heteropolyanions was discussed. For [XW₁₂O₄₀]ⁿ⁻ systems two linear correlation: first, between the experimental redox potential and energies of LUMO orbital; and second, between the experimental redox potential and total energy interaction (calculated between internal tetrahedron (XO₄ⁿ⁻), and rest of Kegging anion skeleton, (W₁₂O₃₆)) were designated. Taking into account the similarity of XW₁₂O₄₀ⁿ⁻ and XMo₁₂O₄₀ⁿ⁻ systems (in geometry and electronic structure), the estimated redox potential of molybdenum heteropolyanions (with X being p block elements) in different solvent were proposed.

Bimetal zeolite imidazolate framework derived Mo0.84Ni0.16-Mo2C@NC nanosphere for overall water splitting in alkaline solution

The bifunctional efficient electrocatalysts for both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) are in urgent need for the advanced overall water splitting (OWS) device. Restricted by the thermodynamic limitations of the catalytic active center for OER and the reaction kinetics limitations induced by the structure of the electrocatalysts, the development of OWS catalysts requires more effort. Herein, a porous carbon-based bimetal electrocatalyst of Mo_0.84Ni_0.16-Mo₂C@NC nanosphere is prepared by hydrothermal treatment of PMo₁₂@PVP@Zn/Ni-ZIF which is synthesized via one-pot self-assembled hydrothermal method. Our study confirms that the Mo-Ni alloy and Mo₂C nanoparticles homogeneously distribute in nitrogen-rich carbon-based materials. Furthermore, the porous structure exposes rich active sites and increases the effective specific area for redox reactions. The obtained Mo_0.84Ni_0.16-Mo₂C@NC catalyst requires low overpotentials of 151 and 285 mV to reach a current density of 10 mA cm^-2 towards the water reduction and oxidation in 1 M KOH solution, respectively, and possesses good catalytic stability for one day. This work introduces an advanced method for the synthesis of the bimetal electrocatalyst.