Zheng Ying Wu

Fabrication of photoluminescent ZnO/SBA-15 through directly dispersing zinc nitrate into the as-prepared mesoporous silica occluded with template

Photoluminescent ZnO/SBA-15 mesoporous materials are prepared by directly grind zinc nitrate into the as-prepared samples occluded with template, and this solvent-free method not only saves time and energy, but also enables a large amount of zinc oxide to be highly dispersed in the channels of mesoporous silica. The resulting composites exhibit photoluminescence (PL) properties with the ZnO quantum confinement, and the dispersed ZnO in SBA-15 illustrates a similar UV emission to crystalline ZnO nanostructures. Besides, this photoluminescence is used to try to detect the nitrosamine content in solution by quenching PL spectra for the first time, suggesting potential applications of ZnO/SBA-15 in sensing carcinogens such as N′-nitrosonornicotine (NNN) in the environment.

Adsorption of nitrogen oxides by the moisture-saturated zeolites in gas stream.

This investigation examined the instantaneous adsorption of NO(x) by moisture-saturated zeolites at ambient temperature. Among the zeolites studied, Faujasite exhibited the highest adsorption capacity owing to its relatively large pore size. Besides, the influence of cation was demonstrated by comparing the adsorption of zeolites with different cation densities (NaX vs. NaY, mesoporous silica MCM-48-like vs. Faujasite) and treatments (ion exchange of NaY with Cu(2+)). For the adsorption of NO, the effects of gas flow rates and pre-adsorbed hydrocarbons such as benzene, acetaldehyde or 1,3-butadiene were evaluated. It was proven that zeolite could efficiently capture nitrogen oxides in gas stream even it had been saturated by moisture, which will be valuable for the protection of environment and public health.