The structure of amorphous precursor species formed under hydrothermal conditions, prior to the onset of crystallization of microporous aluminosilicate zeolites, is determined employing high-energy X-ray diffraction (HEXRD). The investigation, combined with the use of reverse Monte Carlo modelling suggests that even numbered rings, especially 4R (R: ring) and 6R, which are the dominant aluminosilicate rings in zeolite A, have already been produced in the precursor. The model implies that the formation of double 4Rs occurs at the final step of the crystallization of zeolite A.

ZSM-5 and faujasite, which are aluminosilicate zeolites with different compositions, were synthesized without using organic structure-directing agents, and the changes in the medium-range order during the crystallization of ZSM-5 and faujasite were characterized by high-energy X-ray diffraction (HEXRD) technique. It is found that that the amorphous aluminosilicates have larger fraction of 4 membered ring (4R), compared to 6 membered ring (6R) that is the most dominant in amorphous silica. Furthermore, HEXRD measurements reveal that changes in the medium-range order are characteristic for each zeolite although crystallizations of both zeolites proceeded via a similar way: that is, the dissolution of amorphous precursors to solution followed by the nucleation and crystal growth of zeolite from the soluble species. In ZSM-5 crystallization, no major changes in the medium-range order are observed although slight decrease of the fraction of 4R is confirmed. On the other hand, clear changes in the medium-range order, especially on the ordering of 4R and 6R are confirmed in faujasite crystallization.

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Electrospray apparatus, using ionic liquid (1-ethyl-3-methylimidazolium acetate) as a counter electrode, was developed and investigated by the spray current measurement. The current-voltage characteristics were studied using conductive ionic liquid and nonconductive silicone oil. The capturing and neutralizing of ejected droplets on the ionic liquid counter electrode were confirmed by the spray current monitoring. In addition, the electrospray apparatus was evaluated using the empirical formula of current flow characteristics. The obtained exponent value of niq = 0.517 in the electrospray apparatus using the ionic liquid counter electrode was consistent with the exponent value n of ~0.5, which is reported by the standard electrospray set up using a metal counter electrode. The electrospray techniques using ionic liquid as a counter electrode may provide environmentally sustainable processes for the production and functionalization of nanoparticles.