The sputtering of Au targets onto castor oil generates stable spherical gold nanoparticles (AuNPs) of 2.4 to 3.8 nm. The AuNP size increases with the discharge voltage and the mechanism of nucleation and growth are related to the energy of the atoms/clusters ejected from the target.

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Hierarchically porous ZSM-5 was achieved by using a simple bottom-up strategy combining zeolite seeds with imidazolium-based ionic liquids. The bimodal ZSM-5 with hexagonal arranged mesopores (3 nm) shows important activity in the acid catalysis of bulky compounds relative to conventional ZSM-5.

The soot oxidation activity of metallic iron nanoparticles was studied under real diesel engine conditions. Particulate matter (PM) was sampled at distinct temperatures, using fuels containing ferrocene. The results indicated an 80% reduction of accumulated PM using fuels doped with 50 ppm ferrocene at a temperature of 460• C. Temperature-programmed catalytic oxidation tests indicated that PM oxidation in ferrocene-doped fuels starts at an approximately 200• C lower temperature. The transmission electron microscopy (TEM) analysis of the PM revealed that soot agglomerates with and without the presence of Fe showed a similar morphology and that the average diameter of iron nanoparticles is 10 nm. The use of ferrocene-doped diesel fuels increases the speed of PM oxidation significantly, enabling the filter to self-regenerate at the average temperature of the exhaust gases. Moreover, 500 ppm of sulfur in fuels does not reduce the catalytic activity of iron nanoparticles in PM oxidation.

A set of six imidazolium ionic liquids (1a-b, 2a-c, 3), that were solids at room temperature, were characterized by electrical impedance spectroscopy to obtain information about their polarization resistance (R p ), conductivity (s) and charge transfer activation energy (E a ). These experiments were performed at different temperatures in a glass micro-cell, equipped with three platinum electrodes. The observed conductivities were due to charge transfer processes of molecular oxygen at the electrode surface and mass transfer processes within the IL matrix. Higher temperatures resulted for all ionic liquids in increased conductivities. X-Ray diffraction of the ionic liquids 2a-c suggested that a higher degree of supramolecular two-dimensional organization, higher density, is related to an easier oxygen-electrode approximation, lower E a . Two distinct temperatures ranges were observed. The larger conductivity increases in the higher temperature range were explained by melting (ILs 1-2) and fluxional behavior/reorientation phenomena of the ionic liquids and are due to enhanced oxygen diffusion (IL 3). In general, the understanding of imidazolium ionic liquid electrochemical properties could facilitate the development of new applications.