Rod-like cyanophenyl probe molecules nanoconfined to oxide particles: Density of adsorbed surface species

Surface layers have already been observed by broadband dielectric spectroscopy for composite systems formed by adsorption of rod-like cyanophenyl derivates as probe molecules on the surface of oxide particles. In this work, features of the surface layer are reported; samples with different amounts of the probe molecules adsorbed onto oxide (nano) particles were prepared in order to study their interactions with the surface. Thermogravimetric analysis (TGA) was applied to analyze the amount of loaded probe molecules. The density of the surface species n(s) was introduced and its values were estimated from quantitative Fourier transform infrared spectroscopy (FTIR) coupled with TGA. This parameter allows discriminating the composites into several groups assuming a similar interaction of the probe molecules with the hosts of a given group. An influence factor H is further proposed as the ratio of the number of molecules in the surface layer showing a glassy dynamics and the number of molecules adsorbed tightly on the surface of the support: It was found for aerosil composites and used for calculating the maximum filling degree of partially filled silica MCM-41 composites showing only one dielectric process characteristic for glass-forming liquids and a bulk behavior for higher filling degrees

Surface species of the nematic mixture E7 obtained by electrochemical insertion of Li

We studied here the influence of Li+ ions on the benzene rings of nematic mixture E7, which is electrochemically adsorbed onto gold electrode surface, to highlight the ability of this mixture for the applications in the field of the rechargeable Li+-ion batteries. Raman spectra support the changes observed in electrochemical analyses while contact angle measurements show that wetting properties of E7 layer were modified after deposition of this mixture onto gold support and the doping with Li+ ions

Pd-Cu catalysts supported on anion exchange resin for the simultaneous catalytic reduction of nitrate ions and reductive dehalogenation of organochlorinated pollutants from water

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