J.L. Shi

The preparation and photoluminescence properties of ZnO-MCM-41

Abstract ZnO crystallites have been anchored within the pore channels of silica MCM-41 (named ZnO-MCM-41) through a chelation method of Zn2+ by ethyldiamino group (EN) on the inner surface. The structural and elemental composition analyses of the material were characterized by the SAXRD, XRD, BET, XPS and EDS under HRTEM techniques. The ZnO crystallites were about 1.7 nm estimated from the UV–Vis spectra. The bright UV (377 nm), violet (420 nm) and blue–green (480 nm) photoluminescence (PL) bands have been detected. The unfamiliar violet PL band is related to the oxygen vacancies on the ZnO–SiO2 interface traps.

Bilirubin adsorption property of mesoporous silica and amine-grafted mesoporous silica

Nephritic, hepatic and immune failures would lead to the overload of endogenous toxic molecules (e.g. bilirubin, cholic acid, uric acid, creatinine etc.) in human bodies. It is fatal in most cases and extracorporeal blood purification (ECBP) is powerful first-aid therapy. Adsorbents are key parts of ECBP apparatus. Mesoporous silicas should be promising candidates for these medical adsorbents, but there is no report about this. Herein, pure and amine-grafted mesoporous silicas have been applied to adsorb bilirubin, cholic acid, uric acid, creatinine and phenobarbital for the first time. These mesoporous materials show high adsorption capacities for bilirubin and uric acid in phosphate buffer solution (PBS). Effects of pore sizes, amine-modification, temperature and ionic strength on their bilirubin adsorption capacities have been studied in detail.

A vacuum nano-casting route to magnetite cores/ mesoporous silica shell composites

Hollow mesoporous silica spheres with magnetite cores (HMSMC) have been fabricated by Vacuum Nano-casting Route. The amount of magnetite cores and saturation magnetization value can be easily adjusted by changing the concentration of iron nitrate solution used in the synthesis procedure. Furthermore, the as-prepared HMSMCs still maintain narrow mesopore distribution, high surface area and large pore volume after the hollow cores of hollow mesoporous silica spheres were filled with magnetite particles. Specially, when the saturation magnetization value of as-prepared HMSMCs reaches 22.0 emu/g, the surface area and pore volume of corresponding HMSMCs are 149 m2/g and 0.19 cm3/g, respectively, and the pore size is 2.30 nm. The corresponding samples are characterized by X-ray diffraction, N2 sorption isotherms, transmission electron microscopy and vibrating-sample magnetometer.