Effection of pH and molar ratio of formaldehyde and urea on preparation of mesoporous SiO₂ microspheres with polymerization induced colloidal aggregation method

ABSTRACT

Mesoporous SiO₂ microspheres were prepared via polymerization induced colloidal aggregation (PICA) method. Particle size of the mesoporous microspheres was about 6 μm. Mesoporous microspheres with various surface morphology and pore structure were obtained via varying the pH and molar ratio of formaldehyde/urea in PICA process. While pH = 1.2 and molar ratio of formaldehyde/urea = 3, the obtained mesoporous SiO₂ microspheres had the most uniform pore size distribution and the largest specific surface area.

KEYWORDS:

• Mesoporous SiO₂ microspheres
• sol-gel method
• polymerization induced colloidal aggregation (PICA) method

Funding

This work is financially supported by the National Natural Science Foundation of China (21574072, 21675091), the Taishan Young Scholar Program of Shandong Province (tsqn20161027), the Key Research and Development Project of Shandong Province (2016GGX102028, 2016GGX102039, 2017GGX20111), the Project of Shandong Province Higher Educational Science and Technology Program (J15LC20), the People's Livelihood Science and Technology Project of Qingdao (166257nsh, 173378nsh), the Innovation Leader Project of Qingdao (168325zhc), the Postdoctoral Scientific Research Foundation of Qingdao, and the First Class Discipline Project of Shandong Province.