LAUSR

Abstract The solution structure of a gemini surfactant, C22-6-6, associated with various counterions was investigated with small-angle neutron scattering (SANS). Subsequently, C22-6-6 with various counterions (Br−, HC2O4−, C2O42−, CO32−, H2PO4−, HPO42− and OH−) was applied as a structure directing agent (SDA) in the synthesis of hierarchical zeolites. C22-6-6 gemini surfactants form robust prolate (rod) micelles that only exhibit small changes in size with varying counterion, concentration, temperature and salt. Hierarchical MFI successfully crystallized with C22-6-6 associated with various counterions as the SDA. The exception was for HC2O4− and H2PO4− which lowered the pH of the final synthesis solution. Different SDA counterions engender MFI zeolites with various morphologies, such as flat sheets, wave-like sheets, aggregates, micron sized spheres, and change the mesoporosity, total pore volume and silicon to aluminum ratio.