A facile and environmentally friendly method for the synthesis of hollow silica particles in a self-stable dispersion

The fabrication of hollow silica particles is of interest from both academic and application viewpoints. In this paper, we propose a distinctly novel method by which hollow silica particles are successfully fabricated in a self-stable system without any surfactants during a self-consumptive templated process. In detail, it was carried out by adopting a two-step feeding of tetraethoxysilane including initial dropping and subsequent addition of residual TEOS in one batch. The synthesized hollow particles have been extensively characterized using a scanning electron microscope, transmission electron microscope and N(2) sorption analysis. The results indicated that the morphology of the resultant hollow silica particles was governed by simply changing the volume ratio of the precursor added in two steps, the reaction temperature and the concentration of ammonia. Additionally, the mechanism governing the formation of the hollow silica particles is discussed.