Growth characteristics of boehmite-derived ultrafine theta and alpha-alumina particles during phase transformation

Relationship between Crystallite Size and Bond Lengths in Boehmite

“…The transformation temperature of boehmite into a transitional alumina (16) and of -into -alumina (17) increases as boehmite crystallite size increases; the origin of this temperature dependence, however, has not been explained. It could be associated to changes in atom bonds, because detailed studies in natural and synthetic boehmite show di!erent bond lengths in both systems (18,19).…”

Dependence of Boehmite Thermal Evolution on Its Atom Bond Lengths and Crystallite Size

“…When boehmite is annealed, it undergoes a series of polymorphic phase transformations: from boehmite into -alumina and then into -and -alumina, which are known as transitional aluminas, and eventually into -alumina, the thermodynamically most stable alumina phase (15). The transformation of boehmite into -Al O is endothermic and occurs after partial dehydroxylation between 300 and 5503C, while the transformation of transitional aluminas into -Al O is exothermic and requires complete dehydroxylation, which occurs between 800 and 13003C.…”

Catalytic application of 1,3,5-triazine-pentaethylenehexamine polymer-supported palladium nanoparticles in the convenient reduction of nitroarenes with sodium borohydride or hydrazine

“…The average crystallite sizes of powders are calculated using Scherrer's formula. 44,45 The crystallite size calculated from the characteristic peak of Pd (about 2θ = 39.673 …”