MgO and Nb2O5 oxides used as supports for Ru-based catalysts for the methane steam reforming reaction

Nile Tilapia Skin Impregnated with Antibacterial Silver/Titanium Dioxide Compounds

The development of alternative (and free-of-antibiotics) antibacterial and antibiofilm agents is an important strategy to circumvent the resistance of bacteria to antibiotics. Herein, we explore the production of mixed oxides by incorporating silver nanoparticles in titanium dioxide as a silver concentration-dependent antibacterial agent that is further incorporated in Tilapia fish skin (a promising prototype of xenograft), integrating the antibacterial activity of mixed oxide into the intrinsic properties of Tilapia skin. The antibiofilm activity of samples prepared with high concentrations of silver (10 wt% of precursor AgNO3) has been considered a good antibiofilm response. The influence of silver content is also observed with respect to the minimum bactericidal concentration, which is reduced to 3.13 mg/mL with a characteristic kill time in the order of 30 min that is associated with antibiofilm activity in biofilm-forming strains of Staphylococcus aureus. These results indicate that modified Tilapia fish skin acquires antibacterial behavior and can be explored for xenografts with prospective applications in the light-dependent actuation of TiO2-based compounds.

Dry and steam reforming of methane. Comparison and analysis of recently investigated catalytic materials. A short review

In order to produce valuable syngas, industrial processes of dry reforming of methane and steam reforming of methane must be further developed. This paper is focused on reviewing recently examined catalysts, supporting the mentioned technologies. In both processes the most popular active material choice is usually nickel, due to its good availability. On the other hand, noble metals, such as ruthenium, rhodium or platinum, provide better performance, however the solution is not cost-effective. Materials used as a support influence the catalytic activity. Oxides with basic properties, such as MgO, Al2O3, CeO2, are frequently used as carriers. One of the most promising materials for reforming of methane technologies are hydrotalcites, due to adjustable composition, acid-base properties and possibility of incorporation of various metals and complexes.

Nanoceria-Supported Ruthenium(0) Nanoparticles: Highly Active and Stable Catalysts for Hydrogen Evolution from Water

Ruthenium(0) nanoparticles supported on nanoceria (Ru⁰/CeO₂) were prepared by reduction of Ru³⁺ ions on the surface of ceria using aqueous solution of NaBH₄. The Ru⁰/CeO₂ samples were characterized by advanced analytical tools and employed as electrocatalysts on the glassy carbon electrode (GCE) in hydrogen evolution from water. The GCE, modified by Ru⁰/CeO₂ (1.86 wt % Ru), provides an incredible electrocatalytic activity with a high exchange current density of 0.67 mA·cm^-2, low overpotential of 47 mV at j = 10 mA·cm^-2, and small Tafel slope of 41 mV·dec^-1. Moreover, this modified GCE provides an unprecedented long-term stability without changing the onset potential (33 mV) even after 10 000 scans in acidic water splitting at room temperature. The hydrogen gas, evolved during the water splitting using the Ru⁰/CeO₂ (1.86 wt % Ru) electrocatalyst, was also collected. The amount of the evolved H₂ gas matches well with the calculated value, which indicates the achievement of nearly 100% Faradaic efficiency.