Large‐Scale Synthesis of a Porous Co₃O₄ Nanostructure and Its Application in Metastable Intermolecular Composites

Abstract

1IntroductionCompared with conventional energetic materials, metastable intermolecular composites (MICs) exhibit improvedp erformance during energyr elease and ignition.M ICs may be applied in actuation, ignition, propulsion, welding,f luidic, and electro-explosive devicesa tb oth the micro and nanoscales. MICs are preparedb ym ixing nanoparticleso fm etallic oxides (MoO 3 ,C uO, Fe 2 O 3 ,a nd Bi 2 O 3 )w ith aluminum [1][2][3][4].S everal methods have been employed to realizeM ICs, including physical mixing, sol-gel,s putteringo fm ultilayer foils, aero-gel, molecular self-assembly [5][6][7][8][9].W hile each method has its merits,s everal disadvantages have also been obtained. Thus, developing novel, facile, and scalable methods to synthesize MICs with homogeneityi sa ni mportant endeavor.One-dimensional( 1D) nanowires have been used to obtain uniform structure of metal oxide/Al core-shells structure [10][11][12].S uch an approach can improve the homogeneity of the final material and control the fuel/oxidizer interfacial contact area, thereby advancing the performance of the nanocomposites. This approach, which is fully compatible with microelectromechanical systems( MEMS) technology,p rovidesa ne fficient means of producing siliconbased MEMSt oa chieve functional nanoenergetics-on-achip (NoC). NoC is considered essential for many applications of MICs. Transition-metal oxide (Co 3 O 4 )n anostructures have received significant research attention becauseo f their wide range of potentiala pplications. The Al/Co 3 O 4 system has ah igh theoretical heat of reactiono f4 232 Jg Considering the above, we investigated the direct synthesis of porous Co 3 O 4 nanostructure on as ilicon substrate using as impleh ydrothermal approach in combination with heat treatment. The nanostructured Co 3 O 4 showsc omplex structure composedo fn anosheets forming ap ore-network architecture. Then, Al/Co 3 O 4 based MICs were synthesized throughd eposited Al onto the Co 3 O 4 via thermale vaporation. The heat of reaction of Al/Co 3 O 4 was investigated by differential scanning calorimetry.T he exothermic reaction before Al melting was greatly enhanced by the Co 3 O 4 nanostructures.T he facile method can be used to fabricate Al/Co 3 O 4 based MICs on as ilicon substrate, which is very convenient for integrating MICsw ith silicon-basedm icroelectromechanical systems to achieve functionaln anoenergetics-on-a-chip.Abstract:T hree-dimensional nanostructured porous Co 3 O 4 was synthesized on as ilicon substratev ia ah ydrothermal route in conjunction with annealing treatment. The structure and morphology of the obtained Co 3 O 4 samples were systemically examined using field-emission scanning electron microscopy and X-ray diffraction. The Co 3 O 4 structures were composed of nanosheets forming ap ore-network architecture that promoted Al penetrationi nto its inner regions during deposition resulting in enhanced interfacial contact area, which significantly improve metastable intermolecularc omposites (MICs) burning rate and the release of ...

Highly Reactive Thermite Energetic Materials: Preparation, Characterization, and Applications: A Review

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A Facile Preparation and Energetic Characteristics of the Core/Shell CoFe2O4/Al Nanowires Thermite Film

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