Preparation of ZnO nanoparticles in inner porous of SBA-15 and investigation its photoluminescence properties

It was demonstrated that the amino groups of APTS (amino propyl triethoxyl silane)-modified well-ordered hexagonal mesoporous silica structure (SBA-15) can be used for chelation of Zn^2+ on the inner surface of pore walls, while the outer surface was poisoned by Si (CH3)3 groups. Thus ZnO nanoparticles can only form in the pore channels with uniform pore diameter. The structural and elemental composition analyses of the material were characterized by the SAXRD, XRD, atomic absorption analysis and FTIR. UV-Vis spectra of the samples which calcinated at 773 and 873 K were recorded. The UV (380 nm) that is the intrinsic photoluminescence emission of ZnO crystallites and also visible (425 and 421 nm) photoluminescence (PL) bands for at 773 and 873 K samples calcinated were detected respectively which attributed to the defects that are related to the anionic oxygen vacancies. The marked blue shift in the absorption band and UV fluorescence are ascribed to the quantume size effects.