Correlating the Morphological Properties and Structural Organization of Monodisperse Spherical Silica Nanoparticles Grown on a Commercial Silica Surface.
A variety of nanosilicas have been widely used to fabricate rough surfaces with superhydrophobic and superhydrophilic properties. In this context, we prepared mixed silica and mixed nanosilica that were generated by the growth and self-assembly of synthesized monodisperse silica nanospheres (11-30 nm, 363 m(2)  g(-1) ) on the surface of Sylopol-948 and Dispercoll S3030 by using a base-catalyzed sol-gel route. Using this process, the interactions and hierarchical structure between the nano- and microsized synthesized silica particles were studied by changing the amount of tetraethoxysilane. The resulting materials were characterized by BET analysis, small-angle X-ray scattering (SAXS), dynamic light scattering, FTIR spectroscopy, and SEM. The mixed silica presented a higher specific surface area (326 m(2)  g(-1) ), a six-fold higher percentage of (SiO)6 (44-68 %), and a higher amount of silanol groups (14.0-30.7 %) than Sylopol-948 (271 m(2)  g(-1), 42.6 %, and 12.5 %, respectively). The morphological and hierarchical structural differences in the silica nanoparticles synthesized on the surface of commercial silica (micrometric or nanometric) were identified by SAXS. Mixed micrometric silica exhibited a higher degree of structural organization between particles than mixed nanosilica.
Departamento de Engenharia Química, Universidade Federal Rio Grande do Sul, Rua Engenheiro Luis Englert, CEP 90040-040, Porto Alegre, RS (Brazil).
Yolice P
YP
Moreno
LNLS - Laboratório Nacional de Luz Síncrotron, CEP 13083-970, Caixa Postal 6192, Campinas, SP (Brazil).
Mateus B
MB
Cardoso
Instituto Tecnológico Metropolitano, Robledo, Calle 73 # 76A 354, bloque F, Medellín (Colombia).
Edwin A
EA
Moncada
Departamento de Engenharia Química, Universidade Federal Rio Grande do Sul, Av. Bento Gonçalves, 9500 Porto Alegre, RS (Brazil). jhzds@iq.ufrgs.br.
João H Z
JH
dos Santos
nanoparticles; self-assembly; small-angle X-ray scattering; sol-gel processes; surface properties