Reactive characterization of anhydrous iodine (v) oxide (I2O5) with aluminum: amorphous versus crystalline microstructures.

Iodine pentoxide (I 2 O 5 ) is typically synthesized by dehydration of iodic acid such that the produced material inherently includes hydrated iodic acid species that facilitate further water absorption when exposed to ambient environments. This is a detrimental property for I 2 O 5 powder used in energetic systems. A dry-approach for synthesizing I 2 O 5 with either crystalline (nano C I 2 O 5 ) or amorphous (nano A I 2 O 5 ) structure was used for this study and compared to the commercially available material. This synthesis approach enabled isolation of the microstructure as a variable to better understand water absorption behavior of I 2 O 5 and associated reactivity. Material characterization included BET, SEM, TEM, and XRD as well as equilibrium analyses using DSC and TGA along with flame speeds. Results show that nano C I 2 O 5 reacts less with atmospheric water and has a more anhydrous behavior than the crystalline I 2 O 5 powder commercially available. The nano A I 2 O 5 also produced a distinct pre-ignition reaction (PIR) and evidence for smaller PIRs are shown for all mixtures of Al with I 2 O 5 . These properties along with increased specific surface area of the nano C I 2 O 5 and nano A I 2 O increased reactivity and enhanced combustion with Al when compared with commercial I 2 O 5 . [ABSTRACT FROM AUTHOR]