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Under the mediation of a rough glass surface (RGS), formation of vesicles was realized from a micellar solution of only a simple anionic single-tailed surfactant (STS), sodium dodecylsulfate (SDS), to form a mixed solution of micelles and vesicles. Interestingly, the SDS vesicles formed in the solution displayed good stability upon long-term storage, exposure to high temperature, freeze–thawing, and high salinity after the RGS removal. Adsorption and water contact angle measurements demonstrated that SDS could adsorb on the RGS to form bilayers in which the molecular packing parameter of SDS was in the range of 1/2–1. The bilayer adsorption and the roughness of the solid surface played an important role in vesicle formation. AFM observations suggested that the alkyl tails of SDS in the vesicular bilayer membranes were partially interdigitated, and molecular dynamics simulations revealed that the partially interdigitated bilayer structure is crucial for the formation and stability of the SDS vesicles. This work contributes to the understanding of the nature of vesicle systems.

Inorganic layered double hydroxide (LDH) single-layer nanosheets (SLNSs) are traditionally synthesized with the assistance of organic chemicals or in organic solvents, resulting in organic-coated SLNSs or organic dispersions of SLNSs, which may limit their potential applications. Herein, we report, for the first time, a simple aqueous synthetic route to naked (uncoated) LDH SLNSs; this route, which is termed the PWD route for simplicity, includes three steps: aqueous coprecipitation, water-washing, and redispersion in water. The obtained LDH SLNSs were characterized using TEM, AFM, XRD, and dynamic light scattering techniques, and the stability of the LDH SLNS dispersions was determined. Moreover, the co-assemblies of the LDH SLNSs with negatively charged guests, sodium cholate and graphene oxide, were investigated. Results showed that the SLNSs can remain stable (i.e., without layer-by-layer stacking) for a period of time, depending on temperature, and can be directly used as building blocks for functional materials. This new route has many advantages including its simple operation, environmental friendliness, low cost, and ease of large-scale application.

Self-organized pattern of stearic acid (SA) and Eu(TTA) 3 Phen in a core/ring microstructure and the dewetting were observed by atomic force microscopy (AFM). Here TTA and Phen denote the β-diketone ligand thenoyltrifluoroacetylacetone and the synergistic ligand 1,10-phenanthroline. The core/ring microstructure obtained at low compression speed could be well kept after transfer to solid substrates and kept in humid surrounding. Otherwise dewetting of the microstructure resulting from the shrinkage of the SA core occurred after 1 h, leading to a gap about 200 nm between the core and ring. This work is helpful for further understanding the stability of self-organized microstructure in Langmuir–Blodgett (LB) films with double components.

Fluorescent microcapsules doped with europium β-diketone complex were previously fabricated by stepwise adsorption of polyelectrolytes and europium complex using the layer-by-layer (LbL) technique [Chem. Commun. (2007) 1547–1549]. In this work, the influence of thermal treatment on the morphology of rare earth-doped microcapsules was studied by atomic force microscopy (AFM). Remarkable shrinking, increase of wall thickness and decrease of surface roughness were observed after heating the rare earth-doped microcapsules until 70 °C for 30 min. Intense red light emission at 612.0 nm of the microcapsules could be clearly observed by bare eyes after thermal treatment. Diameter variation of the luminescent microcapsules induced by annealing is attributed to the molecular rearrangement of polyelectrolytes. Study on the fluorescent microcapsules with various sizes provides guidance in potential application as biological assay reagents or display elements.

The structure and stability of self-assembled monolayers (SAMs) on substrates under certain forces are of great importance to thin films for their applications such as lubrication and adhesion in micromachines, corrosion inhibition, biological sensors, etc. In this paper, we investigate the degradation of arachidic acid (AA) monolayers on the mica surface via in situ tapping mode atomic force microscopy (TM-AFM) by continuously scanning at different humidities. Our results indicate that the degradation of AA monolayers varied along with the changing environmental humidity. The curves on the number of pinholes as a function of scan times and the dependence of the surface coverage on the scan times at varied humidity are also presented in this report. It was also found that the average apparent height of AA monolayers decreased with the increasing relative humidity.

The Langmuir–Blodgett (LB) films of zinc(II)5,10,15,20-tetra[4-oxy(2-stearic acid) porphyrin] (ZnTSPP) was used as ordered molecular template to induce the growth of calcium phosphate crystals. This process at the surface of LB films was monitored in situ by Inverted Phase Contrast Microscopy (IPCM). It was found that the crystal morphologies changed from amorphous to regular crystal with the prolonging of the time. The transformation from unstable octacalcium phosphate (OCP) to the most stable hydroxyapatite (HAp) was confirmed. This process is step by step, which is different from the traditional epitaxial process.

Thin solid films containing luminescent europium complex were fabricated on glass and sol–gel formed TiO 2 surfaces modified by phosphate groups and characterized by electron probe microscopy (EPM), fluorescence microscopy (FM) and UV–vis and photoluminescent (PL) spectroscopy. It was found that the two kinds of luminescent films show different morphologies, the film fabricated on TiO 2 layer is more homogeneous, and the energy absorbed by TiO 2 can be transferred to Eu(III) ions. The thermal and mechanical stability of this inorganic–organic composite material is improved greatly and has important application in electrical and optical devices.

Monolayer aggregation of a series of atypical amphiphilic rare earth complexes REL 3 Phen [RE=Eu(III), Sm(III), Tb(III); L=acac (acetylacetone), TFA (trifluoroacetylacetone), HFA (hexafluoroacetylacetone), TTA (thenoyltrifluoroacetone); Phen=1, 10-phenanthroline] were investigated at the air/liquid interface by π - A isotherms, Brewster angle microscopy (BAM) and transmission electron microscopy (TEM). When the complexes were mixed with arachidic acid (AA), respectively, stable monolayers could be formed. The rare earth complexes could be divided into two classes according to the π - A isotherm shape that whether there was a plateau period or not. Complexes with β-diketones acac, TFA and HFA were in one class, while complexes with the β-diketone TTA were in another. All the rare earth complexes formed microcrystals at the air/liquid interface. However, the former complex microcrystals oriented with the same crystal plane facing to all directions upon compression; while the latter complex microcrystals oriented with the same crystal plane facing to the same direction. Differences between monolayer behaviors of the two classes of complexes were discussed by comparing the structure of β-diketone ligands. A possible structural model of the rare earth complexes in the mixed monolayers with AA at air/liquid interface was proposed.