Combined Flame and Electrodeposition Synthesis of Energetic Coaxial Tungsten-Oxide/Aluminum Nanowire Arrays

• Published in: Nano letters Vol. 13; no. 9; pp. 4346 - 4350
• Main Authors: Dong, Zhizhong, Al-Sharab, Jafar F, Kear, Bernard H, Tse, Stephen D
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 11.09.2013
• Subjects: Aluminum; Aluminum Oxide - chemistry; Anisotropy; Arrays; Combustion; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Electrodeposition; Exact sciences and technology; Low-dimensional structures (superlattices, quantum well structures, multilayers): structure, and nonelectronic properties; Materials science; Microscopy, Electron, Scanning; Nanocrystalline materials; Nanoscale materials and structures: fabrication and characterization; Nanostructure; Nanotechnology; Nanotubes - chemistry; Nanowires; Nanowires - chemistry; Oxides - chemistry; Oxidizers; Physics; Quantum wires; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Synthesis; Thermodynamics; Tungsten - chemistry; Coaxial nanowire; aluminum electrodeposition; thermite; tungsten-oxide nanowire; Tungsten oxide; Monocrystals; Composite materials; Nanocomposites; Anisotropy; Electrodeposition; Nanowires; Nanostructures; Arrays; Nanostructured materials
• ISSN: 1530-6984; 1530-6992
• DOI: 10.1021/nl4021446

A nanostructured thermite composite comprising an array of tungsten-oxide (WO2.9) nanowires (diameters of 20–50 nm and lengths of >10 μm) coated with single-crystal aluminum (thickness of ∼16 nm) has been fabricated. The method involves combined flame synthesis of tungsten-oxide nanowires and ionic-liquid electrodeposition of aluminum. The geometry not only presents an avenue to tailor heat-release characteristics due to anisotropic arrangement of fuel and oxidizer but also eliminates or minimizes the presence of an interfacial Al2O3 passivation layer. Upon ignition, the energetic nanocomposite exhibits strong exothermicity, thereby being useful for fundamental study of aluminothermic reactions as well as enhancing combustion characteristics.