ausblenden:
Schlagwörter:
CONTROLLED DESILICATION; ALUMINUM DISTRIBUTION; ZSM-5 CRYSTALS; ZEOLITE ZSM-5; MFI ZEOLITES; PARTICLES; SPHERES; MICROCAPSULES; NANOPARTICLES; RELEASE
Zusammenfassung:
Hollow mesoporous aluminosilicate particles have been synthesized through a one-pot synthesis without using any cavity-forming template. The hollow particles have mesoporous shells with surface areas up to 1300 m(2) g(-1). The thickness of the shell can be adjusted from about 30 nm to 50 nm by tuning the molar Si/Al ratio and/or variation of the time of hydrothermal treatment. EDX analysis (element mapping) revealed a certain zoning of aluminum in the amorphous aluminosilicate particles investigated. There is an enrichment of Al on the outside of the particles close to the surface. The presence of aluminum appeared to be the key factor for the inhomogeneous dissolution of the aluminosilicate (dissolution of silicon-enriched cores) that leads to the formation of hollow particles