Untangling the Efficient Boron-Initialized Hydroxyl-Terminated Polybutadiene Combustion for High Energetic Solid Propulsion Systems.

Highly energetic boron (B) particles embedded in hydroxyl-terminated polybutadiene (HTPB) thermosetting polymers represent stable solid-state fuel. Laser-heating of levitated B/HTPB and pure HTPB particles in a controlled atmosphere revealed spontaneous ignition of B/HTPB in air, allowing for examination of the exclusive roles of boron. These ignition events are probed via simultaneous spectroscopic diagnostics: Raman and infrared spectroscopy, temporally resolved high-speed optical and infrared cameras, and ultraviolet-visible (UV-vis) spectroscopy.

Exfoliated Magnesium Diboride (MgB) Nanosheets as Solid Fuels.

Magnesium diboride (MgB) has been explored as an alternative fuel to boron (B) due to its high energy density and the additive effect of magnesium (Mg) to promote B combustion. However, the primary oxidation of MgB does not occur unless it decomposes at a high temperature (830 °C), which makes ignition difficult and the reaction slow. Recently, two-dimensional (2D) exfoliated MgB nanosheets have attracted increasing attention due to their unique properties and potential applications in various fields.

Perfluoroalkyl-Functionalized Graphene Oxide as a Multifunctional Additive for Promoting the Energetic Performance of Aluminum.

Aluminum (Al) is a widely used metal fuel for energetic applications ranging from space propulsion and exploration, and materials processing, to power generation for nano- and microdevices due to its high energy density and earth abundance. Recently, the ignition and combustion performance of Al particles were found to be improved by graphene-based additives, such as graphene oxide (GO) and graphene fluoride (GF), as their reactions provide heat to accelerate Al oxidation, gas to reduce particle agglomeration, and fluorine-containing species to remove AlO. However, GF is not only expensive but also hydrophobic with poor mixing compatibility with Al particles.

Effect of Fluoroalkylsilane Surface Functionalization on Boron Combustion.

Boron has been regarded as a promising high-energy fuel due to its high volumetric and gravimetric heating values. However, it remains challenging for boron to attain its theoretical heat of combustion because of the existence of its native boron oxide layer and its high melting and boiling temperatures that delay ignition and inhibit complete combustion. Boron combustion is known to be enhanced by physically adding fluorine-containing chemicals, such as fluoropolymer or metal fluorides, to remove surface boron oxides.

Blocking chemical warfare agent simulants by graphene oxide/polymer multilayer membrane based on hydrogen bonding and size sieving effect.

Chemical warfare agents (CWAs) are toxic materials that cause death by contact with the skin or by respiration. Although studies on detoxification of CWAs have been intensively conducted, studies that block CWAs permeation are rare. In this study, for blocking CWAs, a multilayer thin film composed of linear polyethylenimine (LPEI) and graphene oxide (GO) is simply prepared through a spray-assisted Layer-by-Layer (LbL) assembly process.

UiO-66-NH and Zeolite-Templated Carbon Composites for the Degradation and Adsorption of Nerve Agents.

Composites of metal-organic frameworks and carbon materials have been suggested to be effective materials for the decomposition of chemical warfare agents. In this study, we synthesized UiO-66-NH/zeolite-templated carbon (ZTC) composites for the adsorption and decomposition of the nerve agents sarin and soman. UiO-66-NH/ZTC composites with good dispersion were prepared via a solvothermal method.

Fabrication of Graphene Based Durable Intelligent Personal Protective Clothing for Conventional and Non-Conventional Chemical Threats.

Conventional or non-conventional chemical threat is gaining huge attention due to its unpredictable and mass destructive effects. Typical military protective suits have drawbacks such as high weight, bulky structure, and unpredictable lifetime. A durable, light, and scalable graphene e-fabric was fabricated from CVD-grown graphene by a simple co-lamination method.

Zr(OH)/GO Nanocomposite for the Degradation of Nerve Agent Soman (GD) in High-Humidity Environments.

Zirconium hydroxide, Zr(OH) is known to be highly effective for the degradation of chemical nerve agents. Due to the strong interaction force between Zr(OH) and the adsorbed water, however, Zr(OH) rapidly loses its activity for nerve agents under high-humidity environments, limiting real-world applications. Here, we report a nanocomposite material of Zr(OH) and graphene oxide (GO) which showed enhanced stability in humid environments.