Exploring the influence of mesoporosity in hard carbon-templated hierarchical SAPO-5 for ethanol dehydration

Microporous solid acid catalysts offer a vast amount of control over chemical processes. However, their coveted smaller pores also have several drawbacks, including a limited substrate scope, faster deactivation, and pore blockage. As such, there are significant advantages to introducing mesopores alongside the microporous framework, to create hierarchically porous frameworks. This work explores the influence of adapting our microporous synthetic procedure for silicoaluminophosphate (SAPO-5) to include different shaped carbon nanotemplates. The differing size of the mesopores formed is explored using nitrogen physisorption, transmission electron microscopy and small angle neutron scattering. In this work, we uniquely use small angle neutron scattering for probing hierarchical silicoaluminophosphates synthesised with hard templating methods. Here small angle neutron scattering was able to probe the shape and size of the mesopores and link their accessibility to their catalytic performance. Carbon nanotemplates are used to create hierarchical silicoaluminophosphate materials, with superior catalytic performance to microporous materials. Their hierarchical nature is probed with in-depth microscopy and small-angle neutron scattering.