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Abstract: One-dimensional (1D) silver oxide nanoparticle arrays were synthesized by illuminating the composite Langmuir–Blodgett monolayers of porphyrin derivatives/Ag+ and n-hexadecyl dihydrogen phosphate (n-HDP)/Ag+ deposited on carbon-coated copper grids with daylight and then exposing them to air. Transmission electron microscopy (TEM) observation shows that the nanoparticle size is around 3 nm, with the separation of about 2–3 nm. High-resolution TEM (HRTEM) investigation indicates that the particles are made up of Ag2O. Ag nanorods with the width of 15–35 nm and the length of several hundreds of nanometers were synthesized by irradiating the composite Langmuir monolayers of porphyrin derivatives/Ag+ and n-HDP/Ag+ by UV-light directly at the air/water interface at room temperature. HRTEM image and selected-area electron diffraction (SAED) pattern indicate that the nanorods are single crystals with the (110) face of the face-centered cubic (fcc) silver parallel to the air/water interface. The formation of the 1D arrays and the nanorods should be attributed to the templating effect of the linear supramolecules formed by porphyrin derivative or n-HDP molecules in Langmuir monolayers through non-covalent interactions. [Copyright &y& Elsevier]

Hexadecyl phosphate (HP)/ester stearate (ES)/europium complex hybrid nanostructures were fabricated at the air/liquid interface by absorbing from subphase and co-spreading methods, and characterized by transmission electron microscopy (TEM). Extended wire-like structures with the width of ca. 1 nm and closely packed round domains comprised of 1-nm-wide wire-like structures were observed in TEM micrographs of monolayers formed by spreading the chloroform solution of HP/ES (mole ratio 1:2) onto Eu(bpy)2Cl3(H2O)2 aqueous solution surface and by spreading the mixed chloroform solution of HP/ES/Eu(bpy)2Cl3(H2O)2 (mole ratio 1:2:1) onto pure water surface, respectively. Similar results were obtained for Eu(phen)2Cl3(H2O)2. FTIR spectra of HP, ES and HP/ES/Eu(bpy)2Cl3(H2O)2 casting films reveal that the formation of the linear structure should be ascribed to the hydrogen bond between P=O and P–O–H groups and the electrostatic interaction between the P–O− group in HP and the europium complex cation. A similar result was found at the HP/ES (1:2) monolayer/ferrous complex aqueous solution interface too. [Copyright &y& Elsevier]

The supramolecular assemblies of sandwich-type complex Eu(TPyP)Pc (TPyP: tetrapyridylporphyrin; Pc: phthalocyanine) were fabricated at the air/water and air/Cd2+ aqueous solution interfaces. One-dimensional columns and two-dimensional coordinate framework were formed, respectively, and characterized by surface pressure–area (π–A) isotherms, UV–vis spectra and polarized UV–vis spectra. The orientation angle of macrocycles with respect to the substrate surface is about 38° and 32° for the Langmuir–Blodgett films from pure water and Cd2+ subphase surfaces, respectively. [Copyright &y& Elsevier]

Abstract: Regular one-dimensional (1D) parallel chains composed of CdS nanoparticles with cubic zinc blende crystal structure were prepared at the air/water interface via one-step synthesis and assembly process. These nanostructures were produced through an interfacial reaction between Cd2+ ions in the aqueous solution of cadmium acetate and H2S in the gaseous phase under Langmuir monolayers of 10,12-pentacosadiynoic acid (PDA). It was demonstrated that PDA molecules self-assembled into parallelly aligned linear supermolecules at the air/water interface with the aid of π–π interactions and acted as templates for the formation of the superstructures. The experimental conditions including temperature and reaction time have great influences on the superstructure formation and the parameters of the parallel chains. [Copyright &y& Elsevier]