Synthesis, characterisation and control of faulting in STF/SFF topologies, a new family of intergrowth zeolites

A new family of zeolites, which can be described as intergrowths between the STF and SFF structure types has been prepared. The degree of faulting between the two end-member structures can be varied across the full range of possibilities, from almost pure STF through to almost pure SFF. This control over the faulting in the materials is accomplished by carefully changing the synthesis conditions and by addition of fluoride ions as a mineralising agent, but for the first time using the same structure directing agent and the same framework composition in all preparations. The materials have been characterized by a number of techniques, including X-ray diffraction, transmission electron microscopy and MAS that supports the intergrowth nature of the samples.