zeolites, porous, adsorber, encapsulation, triggered release
Recent advances in hydrothermal synthesis techniques and procedures to modify the surfaces of the particles have led to the development of a new class of material – the NanoZeolites. The availability of porous, nanocrystalline materials has opened up new applications which were until now unserviceable with microcrystalline particles. This paper will provide an overview of the recent advances in zeolite synthesis, and highlight their enhanced properties with three examples from applications either under development or already commercially available. Reducing the mean particle size down from tens of microns to around 100 nm, means an increase in the surface area (per gram of particles) and also increases the kinetics of adsorption/desorption processes. This is put to use in the form of thin film coatings in energy recovery systems. The use of nanozeolites means a reduction in weight (less material required); smaller cross-sections (due to thinner films); enhanced kinetics and hence, higher efficiency of the whole system. Zeolites can also be employed as hosts for functional molecules such as dyes or catalysts. These encapsulated molecules exhibit more stability to chemical, mechanical and thermal influences. Furthermore, the application range of the functional molecule can be extended, e.g. organic dyes in aqueous systems; photochromic dyes in polymers with high flexural modulus. Examples will also be given of how molecules can be released from their encapsulation using UV light or heat as “triggers”.