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Abstract: Several nanostructures composed of fine ZnS nanoparticles was prepared at the air–water interface via reactions between Zn2+ and H2S under monolayers of 5,10,15,20-tetra-4-oxy(2-stearic acid) phenyl porphyrin (TSPP) at room temperature and characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), atomic force microscopy (AFM), UV–vis and fluorescent spectroscopy. It was found that networks and round rings were formed under different conditions, and belts appear in the pores of the networks. After ripening at 60°C, the belts preserve with improved crystallinity of the nanoparticles. After treated at 300°C, the belts preserve, too. The formation of the rings at room temperature should be attributed to the templating effect of liquid films formed by TSPP molecules at the interface, the formation of the belts should be attributed to the attachment of the cubic zinc blende ZnS nanoparticles possibly under the direction of linear supramolecules of TSPP. [Copyright &y& Elsevier]

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]

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]