α‐Fe2O3 nanotubes that can be used as chemical sensors (see Figure) are fabricated by a novel carbon nanotube (CNT) templated synthesis. CNTs are coated with a continuous layer of Fe2O3 nanoparticles by the decomposition of Fe(NO3)3 in a supercritical CO2/ethanol solution. Subsequent removal of the CNTs gives α‐Fe2O3 nanotubes that are highly sensitive to H2S, which makes them attractive materials for chemiluminescent H2S sensors.

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In the present work, several MEEKC systems are studied to assess their suitability for lipophilicity determination of acidic, neutral and basic compounds. Thus, several microemulsion compositions over a wide range of pH values (from 2.0 to 12.0), containing heptane, 1-butanol and different types and amounts of surfactant (sodium dodecyl sulfate or sodium cholate: from 1.3% to 3.3%) are characterized using Abraham's solvation model. The addition of acetonitrile (up to 10%) is also studied, since it increases the resolution of the technique for the most lipophilic compounds. The system coefficients obtained are very similar to those of the 1-octanol/water, used as the reference lipophilicity index, allowing simple and linear correlations between the 1-octanol/water partition values (log P o/w ) and MEEKC mass distribution ratios (log k MEEKC ). Variations in the ME composition (aqueous buffer, surfactant, concentration of ACN) did not significantly affect the similarity of the MEEKC systems to log P o/w partition.

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Pt/CeO2/CNT catalysts were prepared by adsorbing Pt nanoparticles on the supports of CNTs coated with CeO2. The electrocatalytic performances in respect to the electrooxidation of chemisorbed CO were tested using potential step and stripping voltammetry methods under variable sweep rate and temperature conditions. At 10 mV s–1, the CO stripping voltammogram exhibited the peak splitting phenomenon. The oxidation charge and the peak potential of the two voltammetric peaks changed regularly with the number of Pt and CeO2 neighbours, the sweep rate, and the temperature. We considered that the low potential peak originated from the reaction of COads with hydroxyl groups on CeO2 adjacent to Pt sites, while the high potential peak came from the reaction of COads with hydroxyl groups produced on pure Pt. Furthermore, the experimental results of the peak potential against the logarithm of the sweep rate and the logarithm of the current maximum time against the step potential were plotted and intersecting lines with different slopes in high and low potential regions in the plot were observed. The lines intersected at lower potentials on the Pt/CeO2/CNT electrode than on the Pt/CNT electrode, which was attributed to the contribution of hydroxyl groups on CeO2.

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