Hydrothermal Synthesis of Hollow Silica Spheres under Acidic Conditions

• DOI: 10.1021/la200719g
• Publication Date: 2011-05-09T14:36:19Z
• Authors: Qiyu Yu; Pengpeng Wang; Shi Hu; Junfeng Hui; Jing Zhuang; Xun Wang
• Keywords: Surface Properties; Electrochemistry; Temperature; Salts; 02 engineering and technology; Hydrogen-Ion Concentration; Coloring Agents; Silicon Dioxide; 0210 nano-technology; Porosity; Catalysis

It is well-known that silica can be etched in alkaline media or in a unique hydrofluoric acid (HF) solution, which is widely used to prepare various kinds of hollow nanostructures (including silica hollow structures) via silica-templating methods. In our experiments, we found that stöber silica spheres could be etched in generic acidic media in a well-controlled way under hydrothermal conditions, forming well-defined hollow/rattle-type silica spheres. Furthermore, some salts such as NaCl and Na(2)SO(4) were found to be favorable for the formation of hollow/rattle-type silica spheres.