114 research outputs found

    Alcohol-Selective Oxidation in Water under Mild Conditions via a Novel Approach to Hybrid Composite Photocatalysts

    Get PDF
    The oxidation of alcohols to carbonyl compounds in a clean fashion (i.e., with water as a solvent or under solvent-free conditions, and using O2 or H2O2 as the primary oxidant) is the subject of considerable research efforts. A new approach for the selective oxidation of soluble aromatic alcohols in water under mild conditions via a novel composite photocatalyst has been developed. The catalyst is synthesized by grafting 4-(4-(4-hydroxyphenylimino)cyclohexa-2,5dienylideneamino)phenol and silver nanoparticles onto the surface of moderately crystalline titanium dioxide. The titanium dioxide-based composite was first extensively characterized and then employed in the catalytic oxidation of 4-methoxybenzyl alcohol to 4-methoxybenzaldehyde under UV irradiation in water at room temperature. The corresponding aldehyde was obtained with unprecedented high selectivity (up to 86 %). The method is general and opens the route to fabrication of photocatalytic composites based on titanium dioxide functionalized with shuttle organic molecules and metal nanoparticles for a variety of oxidative conversions

    Enhanced heterogeneously catalyzed Suzuki–Miyaura reaction over SiliaCat Pd(0)

    Get PDF
    The SiliaCat Pd(0) solid catalyst can be efficiently employed in the Suzuki–Miyaura cross-coupling of an ample variety of haloarenes, including economically viable chloroarenes. The catalyst can be extensively recycled without loss of activity and with low leaching of valued palladium, opening the route to widespread utilization of the method to afford high yields of biaryls devoid of contaminating by-products

    New neuroprotective effect of lemon integropectin on neuronal cellular model

    Get PDF
    Lemon IntegroPectin obtained via hydrodynamic cavitation of organic lemon processing waste in water shows significant neuroprotective activity in vitro, as first reported in this study in-vestigating the effects of both lemon IntegroPectin and commercial citrus pectin on cell viability, cell morphology, reactive oxygen species (ROS) production, and mitochondria perturbation induced by treatment of neuronal SH-SY5Y human cells with H2O2. Mediated by ROS, including H2O2 and its derivatives, oxidative stress alters numerous cellular processes, such as mitochondrial regulation and cell signaling, propagating cellular injury that leads to incurable neurodegenerative diseases. These results, and the absence of toxicity of this new pectic substance rich in adsorbed flavonoids and terpenes, suggest further studies to investigate its activity in preventing, retarding, or even curing neurological diseases

    Valorisation of Biowastes for the Production of Green Materials Using Chemical Methods

    Get PDF
    With crude oil reserves dwindling, the hunt for a sustainable alternative feedstock for fuels and materials for our society continues to expand. The biorefinery concept has enjoyed both a surge in popularity and also vocal opposition to the idea of diverting food-grade land and crops for this purpose. The idea of using the inevitable wastes arising from biomass processing, particularly farming and food production, is, therefore, gaining more attention as the feedstock for the biorefinery. For the three main components of biomass—carbohydrates, lipids, and proteins—there are long-established processes for using some of these by-products. However, the recent advances in chemical technologies are expanding both the feedstocks available for processing and the products that be obtained. Herein, this review presents some of the more recent developments in processing these molecules for green materials, as well as case studies that bring these technologies and materials together into final products for applied usage

    Characterization of Nanostructured SilicaCat Pd0

    No full text
    Structural investigation on nanostructured SiliaCat Pd0 palladium catalyst sheds light into the origins of the remarkable activity of these new catalytic materials

    Heterogeneous versus Homogeneous Palladium Catalysts for Cross-Coupling Reactions

    No full text
    A large number of immobilized-Pd-catalysts for cross-coupling reactions have been introduced in the last decade. Are the observed catalyzed reactions truly heterogeneous or are they homogeneous due to leached palladium? This account critically addresses the leaching issue by selectively referring to some of the newly developed catalytic systems in an attempt to evaluate said systems based on uniform criteria. The report is concluded by identifying the relevant chemical and structural challenges in the field

    NiGraf: A new nickel-based molecularly doped metal for enhanced water electrolysis

    No full text
    Graphene oxide was 3D entrapped in nickel nanoparticles and the resulting nanostructured material applied as electrocatalyst in both hydrogen and oxygen evolution reactions at room temperature. This establishes a completely new class of catalytic materials, dubbed herein “NiGraf”, which is highly promising towards enhanced alkaline water electrolysis
    • …
    corecore