Exotic Inverse Kinetic Isotopic Effect in the Thermal Decomposition of Levitated Aluminum Iodate Hexahydrate Particles.

Aluminum iodate hexahydrate ([Al(H2O)6](IO3)3(HIO3)2; AIH) represents a novel, oxidizing material for energetic applications. Recently, AIH was synthesized to replace the aluminum oxide passivation layer of aluminum nanoenergetic materials (ALNEM). The design of reactive coatings for ALNEM-doped hydrocarbon fuels in propulsion systems requires fundamental insights of the elementary steps of the decomposition of AIH. Here, through the levitation of single AIH particles in an ultrasonic field, we reveal a three-stage decomposition mechanism initiated by loss of water (H2O) accompanied by an unconventional inverse isotopic effect and ultimate breakdown of AIH into gaseous elements (iodine and oxygen). Hence, AIH coating on aluminum nanoparticles replacing the oxide layer would provide a critical supply of oxygen in direct contact with the metal surface thus enhancing reactivity and reducing ignition delays, further eliminating decades-old obstacles of passivation layers on nanoenergetic materials. These findings demonstrate the potential of AIH to aid in the development of next-generation propulsion systems.

[1]  M. Pantoya,et al.  Discovery of Discrete Stages in the Oxidation of exo-Tetrahydrodicyclopentadiene (C10H16) Droplets Doped with Titanium-Aluminum-Boron Reactive Mixed-Metal Nanopowder. , 2022, The journal of physical chemistry letters.

[2]  N. Rubtsov,et al.  Features of hydrogen and deuterium ignition over noble metals at low pressures , 2020 .

[3]  M. Pantoya,et al.  Oxidation of Levitated Exo-Tetrahydrodicyclo-pentadiene Droplets Doped with Aluminum Nanoparticles. , 2019, The journal of physical chemistry letters.

[4]  M. Pantoya,et al.  Plasma surface treatment of aluminum nanoparticles for energetic material applications , 2019, Combustion and Flame.

[5]  M. Pantoya,et al.  A strategy for increasing the energy release rate of aluminum by replacing the alumina passivation shell with aluminum iodate hexahydrate (AIH) , 2019, Combustion and Flame.

[6]  M. Pantoya,et al.  Improving the Explosive Performance of Aluminum Nanoparticles with Aluminum Iodate Hexahydrate (AIH) , 2018, Scientific Reports.

[7]  M. Pantoya,et al.  Replacing the Al2O3 Shell on Al Particles with an Oxidizing Salt, Aluminum Iodate Hexahydrate. Part II: Synthesis , 2017 .

[8]  M. Pantoya,et al.  Synthesis and Reactive Characterization of Aluminum Iodate Hexahydrate Crystals , 2017 .

[9]  Li Wang,et al.  Al-Nanoparticle-Containing Nanofluid Fuel: Synthesis, Stability, Properties, and Propulsion Performance , 2016 .

[10]  M. Dirmyer,et al.  Evidence of a kinetic isotope effect in nanoaluminum and water combustion. , 2014, Angewandte Chemie.

[11]  M. Pantoya,et al.  Effect of oxide shell growth on nano-aluminum thermite propagation rates , 2012 .

[12]  R. J. Jouet,et al.  Influence of Aluminum Passivation on the Reaction Mechanism: Flame Propagation Studies , 2009 .

[13]  E. Dreizin,et al.  Metal-based reactive nanomaterials , 2009 .

[14]  P. Edwards,et al.  Gold in a metallic divided state--from Faraday to present-day nanoscience. , 2007, Angewandte Chemie.

[15]  Z. Assefa,et al.  Synthesis and Structure of In(IO3)3 and Vibrational Spectroscopy of M(IO3)3 (M = Al, Ga, In) , 2006 .

[16]  E. Dreizin,et al.  Oxidation and melting of aluminum nanopowders. , 2006, The journal of physical chemistry. B.

[17]  T. Mcmahon,et al.  Deuterium isotope effect on the radiatively induced unimolecular dissociation of small cluster ions , 1995 .

[18]  V. Koleva,et al.  Kinetic analysis of the dehydration processes in some iodate hydrates , 1994 .

[19]  R. N. Rogers,et al.  Deuterium isotope effects during HMX combustion: chemical kinetic burn rate control mechanism verified , 1989 .

[20]  P. Sherwood,et al.  Vibrational spectra of compounds in the iodine pentoxide-water system and sodium iodate , 1970 .

[21]  O. Bonner,et al.  Raman Studies of Iodic Acid and Sodium Iodate , 1965 .

[22]  M. Pantoya,et al.  Acid-Base Synthesis of Aluminum Iodate Hexahydrate Powder as a Promising Propellant Oxidizer , 2022, SSRN Electronic Journal.

[23]  M. Pantoya,et al.  Replacing the Al 2 O 3 Shell on Al Particles with an Oxidizing Salt , Aluminum Iodate Hexahydrate . Part I : Reactivity , 2017 .

[24]  A. Kjekshus,et al.  Infrared and Raman Studies of Crystalline I2O5, (IO)2SO4, (IO)2SeO4 and I2O4. , 1981 .

[25]  D. J. Hills,et al.  Single-crystal Raman and infrared study of aluminium trichloride hexa-hydrate , 1978 .

[26]  M. Faraday.  X. The Bakerian Lecture. —Experimental relations of gold (and other metals) to light , 1857, Philosophical Transactions of the Royal Society of London.