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Bio-oils derived from the pyrolysis of lignin-based biomass often contain a variety of oxygenated compounds, which can compromise their usefulness as a fuel. To improve the quality of bio-oil, catalytic hydrodeoxygenation (HDO) is a crucial step that removes oxygen from the oil in the form of water. In this study, we showed that MFI nanosheets are excellent supports for Ru-catalysts. We synthesized highly crystalline MFI nanosheets using a simple hydrothermal seeding procedure; the final material was obtained in 56 h of crystallization. We investigated the activity of Ru supported on different materials. Our findings indicated that Ru supported on hierarchical MFI demonstrated excellent activity in HDO of guaiacol. Our results demonstrated that Ru/ZNS-56 achieved nearly 100% selectivity towards cyclohexane under mild conditions (200 °C, 50 bar H2, 1 h). [ABSTRACT FROM AUTHOR]

The textural, structural, morphological, and acidic properties of TiO2/Al-ZSM-12 zeolite synthesized viathe hydrothermal method and using methyltriethylammonium chloride as a template were studied in this study. The structure, size, and shape of the crystallites, and the acidity of the synthesized materials were investigated in detail using the following methods: XRD, low-temperature nitrogen adsorption–desorption, XRF, FTIR, Raman spectroscopy, DRS UV–Vis, DRIFTS, PL, SEM, TEM, solid-state NMR spectroscopy on 27Al, 1H, 29Si, 1H-29Si and 23Na nuclei, NH3-TPD, TG, DSC, DTA, FTIR-Py, FTIR-2,6-dTBP, FTIR-CD3CN, and DRIFTS-acid. The presence of tetrahedral titanium in the TiO2/Al-ZSM-12 zeolite was confirmed by Raman spectroscopy, DRIFT, and 29Si NMR. It was revealed that the crystallites of the TiO2/Al-ZSM-12 zeolite, elongated along the b axis, had a higher acidity compared to the unsubstituted zeolite Al-ZSM-12. The oxidative catalytic activity of the TiO2/Al-ZSM-12 zeolite was studied in the photoinduced decomposition of the crystal violet dye and it was found that the reaction proceeds most efficiently in the presence of H2O2 as an oxidizing agent and TiO2/Al-ZSM-12 as a catalyst (PCA = 0.157%∙min−1). [ABSTRACT FROM AUTHOR]

The dry reforming of methane to syngas (DRM) is of increasing significance concerning, first, the production of raw materials for commercial organic/petrochemical syntheses and for hydrogen energetic, and, second, the utilization of two most harmful greenhouse gases. Herein, new SmCoO3-based DRM catalysts derived from heterometallic precursors and operated without preliminary reduction are reported. For the first time, the effect of supercritical fluids-assisted modification of the SmCoO3-derived catalysts combined with the re-oxidation of spent catalysts to SmCoO3 onto its long-term performance was studied. In particular, the modification of heterometallic precursors by supercritical antisolvent precipitation (SAS) considerably decreases coke formation upon the exploitation of the derived SmCoO3 sample. Moreover, the re-oxidation of the corresponding spent catalysts followed by pre-heating under N2 affords catalysts that stably provide syngas yields of 88–95% for at least 41 h at 900 °C. The achieved yields are among the highest ones currently reported for DRM catalysts derived from both LnMO3 perovskites and related oxides. The origins of such good performance are discussed. Given the simplicity and availability of all the applied methods and chemicals, this result opens prospects for exploiting SAS in the design of efficient DRM catalysts. [ABSTRACT FROM AUTHOR]

Carboxycymantrene CymCOOH (Cym = (η5‐C5H4)Mn (CO)3) was applied to assemble a series of uncommon Cd‐Mn carboxylate complexes comprising 1D‐polynuclear [Cd (OOCCym)(acac)]n (1) as well as oligonuclear species, [Cd2(OOCCym)4(EtOH)4)] (2), [Cd (OOCCym)2(bpy)(H2O] (3, bpy = 2,2′‐bipyridine) and [Cd (OOCCym)2(phen)2]·EtOH (4, phen = 1,10‐phenantroline). Compound 2 was found to be a product of irreversible SCSC transition from [Cd2(OOCCym)4(EtOH)3(H2O)]·EtOH (2_100K) initially formed in corresponding syntheses. This transition is accompanied by two‐fold decrease in cell volume and increase in cell symmetry. Recrystallyzation of 2–4 from common organic solvents affects the nuclearity of products (in case of 2 and 3) or subtly alters the structure of [Cd (OOCCym)2(phen)2] units (4). The optimal Cd to Mn ratio inspired studying solid‐state thermal decomposition of 2–4 as a route to CdMn2O4‐based ceramics. As a result, oxide samples with a predominance of tetragonal (Cd1‐xMnx)Mn2O4 spinel have been prepared and characterized by powder XRD, SEM, EDX, and IR revealing the interplay between the preparation technique and the features of morphology and composition. The retaining of Cd to Mn ratio upon recrystallyzation of 2–4 implies possibility of further elaboration of CdMn2O4‐based materials in various morphologies (polycrystalline ones, films, etc.). Notably, 2–4 is also the first series of related heterometallic Cd‐Mn complexes being studied as individual precursors for CdMn2O4‐based oxide systems. [ABSTRACT FROM AUTHOR]

A series of bis-cyclometalated iridium(III) complexes, [Ir(LH)2(H2dcbpy)][PF6] ( 1), [Ir(LMe)2(H2dcbpy)][PF6] ( 2), and [Ir(LPh)2(H2dcbpy)][PF6] ( 3), where LH = 1-H-2-phenylbenzimidazole, LMe = 1-methyl-2-phenylbenzimidazole, LPh = 1,2-diphenylbenzimidazole, and H2dcbpy = 2,2′-bipyridine-4,4′-dicarboxylic acid, has been synthesized and fully characterized by elemental analysis, 1H and 31P NMR spectroscopy, mass spectrometry, and single-crystal X-ray analysis. The complexes show strong luminescence in the yellow-orange region in ethanol at room temperature (quantum yield is up to 22 %), and absorb light up to 550 nm with molar absorptivities of 1500-2000 M-1 cm-1. Complexes 1 and 2 possess very similar optical properties, whereas the introduction of the phenyl ring (complex 3) causes a hypsochromic shift (≈ 30 nm) of the luminescent maximum as well as resulting in an almost 50 % increase in the extinction coefficient at 490 nm compared with 1 and 2. A dye-sensitized solar cell (DSSC) based on complex 3 exhibits a short-circuit photocurrent of 2.8 mA cm-2, an open-circuit photovoltage of 0.44 V, and a power conversion efficiency of 0.7 %. [ABSTRACT FROM AUTHOR]

[Display omitted] A new method for the synthesis of nanosized ZSM-5 zeolite with the MFI structure in the proton form is reported. The material was synthesized by the hydrothermal-microwave method and characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, atomic force microscopy, low-temperature nitrogen physisorption, thermal desorption of ammonia and solid- state 27Al NMR. The synthesized material is formed by zeolite particles of 30–80 nm in size, which ensures its high specific surface area, pore volume and interparticle porosity. [ABSTRACT FROM AUTHOR]

The dry reforming of methane to syngas (DRM) is of increasing significance concerning, first, the production of raw materials for commercial organic/petrochemical syntheses and for hydrogen energetic, and, second, the utilization of two most harmful greenhouse gases. Herein, new SmCoO 3 -based DRM catalysts derived from heterometallic precursors and operated without preliminary reduction are reported. For the first time, the effect of supercritical fluids-assisted modification of the SmCoO 3 -derived catalysts combined with the re-oxidation of spent catalysts to SmCoO 3 onto its long-term performance was studied. In particular, the modification of heterometallic precursors by supercritical antisolvent precipitation (SAS) considerably decreases coke formation upon the exploitation of the derived SmCoO 3 sample. Moreover, the re-oxidation of the corresponding spent catalysts followed by pre-heating under N 2 affords catalysts that stably provide syngas yields of 88-95% for at least 41 h at 900 °C. The achieved yields are among the highest ones currently reported for DRM catalysts derived from both LnMO 3 perovskites and related oxides. The origins of such good performance are discussed. Given the simplicity and availability of all the applied methods and chemicals, this result opens prospects for exploiting SAS in the design of efficient DRM catalysts.