Zhilei Yin

The study on formation of the reversed micelle in extraction system of primary amine N1923 sulfate

The formation of reversed micelles in extraction systems of primary amine N1923 sulfate and its effect on the extraction mechanism have been investigated by the determination of the interfacial tension and the electrical conductivity in the organic phase. It has been proved by infrared spectroscopy and TEM imaging that the ammonium salt can form a reversed micelle or microemulsion. In addition, theoretical calculations are carried out in order to study further the microstructure of the reversed micelles. We are able to rationalize the unusual features of this extraction system that are found in our experiments.

One-step self-assembled synthesis of CuO with tunable hierarchical structures and their electrocatalytic properties for nitrite oxidation in aqueous media

Controlled synthesis of CuO with various hierarchical structures consisting of self-organized nanoparticles is realized by using n-octylamine (OLA) as a structure inducing agent via a facile hydrothermal synthetic method. The growth and assemblage of CuO can be finely tuned by selecting the preparative parameters. In particular, it is found that the degree of the hierarchical organization can be modulated by simply changing the amount of the n-octylamine and CuO nanoparticles exhibit self-assembled two-dimensional (2D) sheet-like, three-dimensional (3D) disk-like and bowknot-like architectures, respectively. In the present case, OLA serves as a capping surfactant that can modulate growth of CuO nanocrystals via hydrophobic forces between the OLA molecules. CuO nanoparticles can be self-assembled into different complex architectures depending on the strength of hydrophobic forces. Hierarchical sphere-like CuO assembled from nanorods can also be easily fabricated by adjusting the starting NaOH to CuCl2 volume ratio, in which OLA serves not only as the structure-directing agent, but also as a weak base agent to produce hydroxyl anions. The electrochemical performances of the as-synthesized different products for sensing nitrite oxidation are evaluated. The results reveal that the electrocatalytic activity is related to the secondary nanostructures. Compared to the others, the bowknot-shaped and sphere-shaped CuO products exhibit excellent electrocatalytic activity toward nitrite oxidation and fast current response in nitrite sensing because of their peculiar hierarchical structures with high BET surface areas and well-ordered pores.

Self-assemblies of the different morphology ultrafine barium sulfate in situ interface

Abstract Different morphologies of BaSO 4 nanocrystals including nanoparticles and short rods and long fibers were prepared via the static organic/aqueous biphase boundary at the room temperature. The organic phase was a containing primary amine sulfate solution, while the aqueous phase was a solution of Ba 2+ . The effect of [SO 4 2− ]/[Ba 2+ ] molar ratios on the BaSO 4 growth process was studied principally by TEM. In addition, it was found that the diluent polarity can also affect self-assembly process of BaSO 4 crystals at the interface. The possible mechanism of nanocrystalline BaSO 4 self-assembly is discussed.