Synthesis of three-dimensionally ordered macroporous SiO_2 by colloidal crystal template method

Three-dimensionally ordered macroporous(3DOM) SiO2 materials were synthesized by using colloid crystal template which was assembled by centrifugation of polystyrene spheres with 480nm diameter.The sol from tetraetoxysilane was filled in the voids between spheres,and transformed into gel in-situ.The template was removed by calcination.The sample had a hexagonally well-ordered array as shown by SEM observation.The diameter of macroporores was 360 nm corresponding to a shrinkage of 25%.The macropores kept three-dimensionally interconnected macroporous networks through small windows.The walls of pores contained the mesoporous structure with a narrow pore size distribution in 3~4nm according to the result of N2 adsorption-desorption.The XRD spectrum showed that the sample consisted of amorphous SiO2.