Quenching of zinc phthalocyanine excited states by viologen surfactant assemblies——The influence of microenvironment

A series of functional surfactants of N-alkyl-N'-butyl viologens has been synthesized. The quenching of excited singlet and triplet states of zinc phthalocyanine was studied in DMSO and in mixed micelles containing the functional surfactant as one and cationic cetyl trimethylam- monium bromide(CTAB),anionic sodium dodecylsulfate(SDS)and neutral TX-100 surfactant as the other component.Fluorescence quenching and laser photolysis studies indicate that the functional surfactants are solubilized at different sites in micelles,the process depends on chain length and exerts great influence on the quenching of zinc phthalocyanine excited states.

Comparative studies on molecular induced aggregation of hepta-imidazoliumyl-β-cyclodextrin towards anionic surfactants

A β cyclodextrin derivative bearing seven cationic arms and its singly charged analogue, i.e., per-6- deoxy-f-（1-methylimidazol-3-ium-3-yl）-β-cyclodextrin （3） and mono-fi-deoxy-6-（1-methylimidazol- 3-ium-3-yl）-β-cyclodextrin （4） were synthesized and fully characterized. Their induced aggregation behaviours towards two anionic surfactant, that is, sodium dodecyl sulfonate （SDS） and dioctyl sodium sulfosuccinate （Aerosol OT, AOT）, were investigated by UV-vis, NMR, Zeta-potential, dynamic light scattering （DLS）, and transmission electron microscopy. The results revealed that host 3 can induce the molecular aggregation of anionic surfactant at concentration far lower than its original CAC, leading to the larger diameter, the narrower size distribution and the higher thermal stability of the induced aggregate towards the anionic surfactant possessing more hydrophobic tails.

Impact of an ionic surfactant on the ion transfer behaviors at meso-liquid/liquid interface arrays

The influence of ionic surfactants,cetyltrimethylammonium bromide（CTAB）,self-assembled within silica-nanochannels of a hybrid mesoporous silica membrane（HMSM） on simple ion transfer（IT）behaviors at the meso-water/1,2-dichloroethane（W/DCE） interface arrays supported by such a HMSM was investigated by voltammetry for the first time.Significantly,it is found that the CTAB in HMSM can dramatically enhance the peak-current responses corresponding to ITs of some anions and even lower their Gibbs transfer energies from W to DCE,which could be ascribed to an anion-exchange process between anions and the bromide of CTAB associated with partial ion-dehydration induced by the CTAB.This work will provide a new strategy to study anion transfer processes and improve the electroanalytical performance for anion detection at the liquid/liquid interface.

Template preparation of twisted nanoparticles of mesoporous silica

Optical isomers of N-lauroyl-L-（Or-D-） alanine sodium salt {C12-L-（Or-D-）AIaS} surfactants were used for the preparation of mesoporous silica nanoparticles with a twisted hexagonal rod-like morphology. Thermogravimetric analysis （TGA） was used to determine the temperature for template removal. Circular dichroism （CD） spectra of the surfactant solution with various compositions illustrated the formation and supramolecular assembly of protein-like molecular architecture leading to formation of twisted nanopar- ticles. Scanning electron microscopy （SEM）, high-resolution transmission electron microscopy （HRTEM） and X-ray powder diffraction （XRD） patterns of these as-synthesized mesoporous silica confirmed that the twisted morphology of these nanoparticles was closely related to the supramolecular-assembled complex of amino acid surfactants.