Hollow ZnO/Zn2SiO4/SiO2 sub-microspheres with mesoporous shells: Synthesis, characterization, adsorption and photoluminescence

The multifunctional versatile ZnO/Zn2SiO4/SiO2 hollow microspheres with porous structures on the shells are successfully fabricated by the sequential deposition of amino-functionalized SiO2 and then ZnO layers on the prepared polystyrene (PS) colloidal templates, and the subsequent calcination process. The formation of hollow morphology was confirmed by scanning electron microscope (SEM) and transmission electron microscope (TEM). Nitrogen sorption measurements also verify the presence of the mesoporous structure scattered on the shells. The application of the absorption capacity to remove toxic metal ions in water is performed. Furthermore, the photoluminescence (PL) results indicate that hollow composites prepared in our experiment have excellent optical properties. The origin of various PL bands is discussed as well. The high surface areas, together with void interiors and mesoporous walls make composites an efficient adsorbent and promising platform for optoelectronics and nanomedicine applications. (C) 2012 Elsevier B.V. All rights reserved.