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This work aimed to determine the carrier effect on anisole hydrodeoxygenation (HDO, batch reactor at 573 K, and 4 MPa of H2) on 5 wt% Ni catalysts on TiO2 and TiO2-ZrO2 carriers. Besides, a TiO2-supported Ru-doped catalyst was also tested. Differences in surface acid sites, Ni reducibility, oxygen vacancies, and interactions among metals and support were detected. For instance, Ru addition promoted Ni reducibility due to improved hydrogen adsorption and subsequent spillover effect. Methoxycyclohexane and cyclohexanol were the main products over Ni/TiO2. Ru incorporation increased the initial reaction rate (×3) compared with non-doped Ni/TiO2 favoring benzene selectivity. Ni/TiO2-ZrO2 exhibited higher HDO activity and enhanced acidity than the material supported on TiO2, and high deoxygenated compounds yield a fully hydrogenated compound (cyclohexane) as well. Therefore, it was possible to promote the desired reaction pathway to relevant chemical compounds that are associated with both the support type and the metallic phase composition. [ABSTRACT FROM AUTHOR]

Surfactant addition during support synthesis resulted in materials with defined porosity, smaller particle size, and the absence of segregated ZrO2 and TiO2 crystalline phases at least to the XRD detection limit. The data obtained by N2 physisorption showed improved textural properties compared with the individual pure oxides. The Ultraviolet–visible (UV–Vis) diffuse spectroscopy revealed broadband assigned to the mixed-phase. Meanwhile, the micrographs obtained by transmission electron microscopy showed nanometric domains of crystallinity and a worm-like morphology in all the samples. Raman spectroscopy showed the possible formation of the TiZrO4 forming the mixed oxides support. The chemical analysis performed by ICP-OES corroborates the expected equimolar relation Zr/Ti and the atomic ratio Ni/(Ni + W) approximately equal to 0.31. The support properties intrinsically influenced the WS2 nano slabs, as observed by TEM micrographs for the NiW/ZT-x sulfided series. The XPS analysis revealed that sulfidation degree increases and the highest amount of NiWS phase among all the materials are observed when the NiW system is deposited on the mixed oxides prepared with pluronic. The latter was also related to the reaction rates, where the sulfided NiW/ZT-x catalysts presented higher values than the NiW/ZT reference material. NiW/ZT-P sulfided sample showed the maximum reaction rate among the series studied. [ABSTRACT FROM AUTHOR]

A series of Al-doped Na-TiO2 nanorods (AlTi-nR-x) varying the Al2O3/TiO2 (Al/Ti) ratio was synthesized by hydrothermal method. TEM results revealed well-defined nanorod like shape morphology. XPS results confirmed the presence of Al inside the samples and a slight increase in electron density around the Ti atom. Calcined materials were evaluated in the CO2 hydrogenation (HYD) in a continuous flow-microreactor at 280–340 °C under atmospheric pressure. Results from this work exposed that all AlTi-nR-x materials have great potential to be used as CO2 HYD catalysts. However, the best catalytic performance was obtained with the AlTi-nR-0.5 catalysts, which also displayed high selectivity (82%) towards methanol. [ABSTRACT FROM AUTHOR]

In this study, it is proposed the incorporation of MgO into of SBA-15 via the direct synthesis different atomic ratios of Si/Mg (20, 40 and 80). Although the incorporation of Mg did not affect the mesoporous character of SBA-based materials, it was found dramatic changes in the SBA-15 characteristic honeycomb structure even after the incorporation of small amount of Mg. The creation of more basic sites in SBA-15, because of the addition of Mg, improved ODH conversion of n-octane with respect to SBA-15, used as reference. Sample with a Si/Mg molar ratio of 20 showed the best catalytic performance in the oxidative dehydrogenation of n-octane, while the sample with a Si/Mg molar ratio of 40 achieve the highest productions of olefins. [ABSTRACT FROM AUTHOR]

A capable one-step method, femtosecond laser ablation of solids in liquids, was successfully applied to prepare lithium metal nanoparticles to mitigate the initial capacity loss and improve the electrochemical performance of a graphite-based electrode as a Li-host anode. Remarkably, according to the physicochemical characterization, this advanced optical method allowed to obtain uniform spheroidal and crystalline Li nanoparticles with an average particle size <20 nm. These novel ultrafine Li nanoparticles significantly decrease the initial capacity loss of a graphite-based anode, leading to reach high coulombic efficiency (>99 %), good specific charge capacity (322 mAh/g), and superior capacity retention (96 %) at an applied current density of 100 mA g -1 after 200 cycles., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)