Promoting Superbasicity Generation on Mesoporous Silica by Precoating a Zirconia Layer

• 1、State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemistry and Chemical Engineering, Nanjing University of Technology, NanJing 210009
• 2、State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemistry and Chemical Engineering, Nanjing University of Technology, Nanjing 210009

Abstract：Mesoporous solid superbases can catalyze diverse reactions under mild conditions, and attract much attention from researchers. Due to the reaction between strongly basic species and silica, the development of basic materials based on mesoporous silicas remains a challenge. In this paper，a multicoating strategy was utilized to generate strong basicity on mesoporous silica SBA-15 by precoating a zirconia layer before modification with base precursor potassium nitrate. Such a zirconia interlayer plays a double role by promoting the decomposition of potassium nitrate and by improving alkali-resistance of mesoporous silica host. A nice layer of zirconia can be formed in mesoporous silica when the zirconia content reaches 30 wt%. The decomposition temperature of potassium nitrate decreased from 700℃ on unmodified SBA-15 to 500℃ after zirconia coating. The obtained material exhibits ordered mesoporous structure and the high base strength of 27.0, indicating the successful fabrication of mesoporous solid superbase.

Keywords： mesoporous solid superbase zirconia alkali-resistance SBA-15 potassium nitrate