Tie-Zhen Ren

Surfactant-assisted preparation of hollow microspheres of mesoporous TiO2

Abstract Hollow microspheres of mesoporous titania with a thin shell of anatase structure have been prepared by a simple procedure of surfactant poly(ethylene oxide) assisted nanoparticle assembly in nonaqueous system. A high surface area of 378 m 2 /g and pore volume of 0.34 cm 3 /g was obtained in the as-prepared sample with pore size of 2.6 nm. A large number of surface hydroxyl groups and a reduced band gap were found, which should be significant for multi-functionalisation of the surface and photocatalysis applications. A formation mechanism of hollow microspheres was proposed.

A simple method to synthesise single-crystalline manganese oxide nanowires

Single-crystalline nanowires of hexagonal γ-MnO2 phase have been prepared by a simple method in which the commercial granular γ-MnO2 powders were hydrothermally treated in water or ammonia solution at 120–160 °C. The diameters of the γ-MnO2 nanowires are 5–50 nm and the lengths up to several tens of micrometers. Calcination of γ-MnO2 nanowires at the temperature range of 400–500 °C and above 600 °C results in, respectively, the production of single phases of β-MnO2 and α-Mn2O3 crystals, while the nanofibrous morphologies persist. These 1-D nanostructured manganese oxides are expected to have possible novel properties and wide applications.

Simple approach to highly oriented ZnO nanowire arrays: large-scale growth, photoluminescence and photocatalytic properties

A simple and low-cost soft route has been developed to the direct large-scale production of highly oriented ZnO nanowire arrays at 60 °C. It has been found that the growth of well-aligned ZnO nanowire arrays is dependent on several parameters, such as the reaction time and the concentration of ammonium ions. The environmentally benign ZnO nanowires obtained, with significant photoluminescence property and interesting photocatalytic activity, are single crystals and have a low defect concentration, which could be expected to find promising potential for optoelectronic and environmental application.

Thermally stable macroporous zirconium phosphates with supermicroporous walls: a self-formation phenomenon of hierarchy

A self-formation phenomenon leading to the hierarchically thermally stable macroporous zirconium phosphates with amorphous supermicroporous walls from the precursors of zirconium propoxide and orthophosphoric acid solution was observed.