Morphology high-porosity particles

Tor powder synthesis a large variety of methods is available, for example mixed-oxide solution precipitation or emulsion precipitation. Figure 8.11 shows as an example a (Y,Gd)202 powder prepared by three different precipitation techniques. The powders obtained ate different in particle morphology as well as in particle size. Powders prepared by the citrate and the oxalate precipitation techniques are strongly agglomerated [14], From powders derived in this way, compacts are formed. These powder compacts demonstrate total luminescent properties, but have still low light output due to the high porosity of about 50 vol.%. 

In summary of foam-spray drying, all available literature results confirm a strong effect of feed foaming on final product properties of porous and skin-forming materials, for example, an increase of Sauter mean diameter and porosity of the products decrease of bulk, tap density, and apparent density and effect on particle morphology. Foam-spray drying enhances retention of highly volatile substances and... 

Belbekhouch et al. [62] developed cellulose films with a focus on their application as gas barriers. Authors have produced cellulose films in the form of whiskers and MCC and investigated the effect of particle morphology on the transportation gas properties (carbon, nitrogen dioxide, and oxygen). It was observed that the cellulose films are more permeable to gasses when compared with the films of MCC, due to its high porosity provided by the crystalline nanoparticles. 

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