Seek and Destroy: New Material Defeats Chemical Agents

Courtesy Photo | A scientist from the Edgewood Chemical Biological Center (ECBC) separates metal-organic framework (MOF) material from an aluminum surface after electrospinning it. Electrospinning turns a liquid polymer solution into many nanofibers that provide a surface to deposit MOFs. Image courtesy of ECBC.  

FORT BELVOIR, VA, UNITED STATES

04.04.2017

Courtesy Story

Defense Threat Reduction Agency's Chemical and Biological Technologies Department

When chemical agents are deployed, warfighters have little time to react. A few seconds can mean the difference between life and death, requiring protection to be efficient and effective. The Defense Threat Reduction Agency’s Joint Science and Technology Office, in conjunction with Edgewood Chemical Biological Center, Northwestern University and North Carolina State University, is tackling this need by developing a new, more efficient material utilizing chemically reactive metal-organic frameworks (MOFs) to protect warfighters from harmful chemical agents.

Today’s warfighter chem-bio suit contains carbon beads that isolate chemical warfare agents (CWA). However, carbon beads add bulk, weight and moisture resistance, leading to a considerable thermal burden. The new MOFs in development are crystalline, created by linking inorganic and organic materials by strong bonds. The resulting structure is much more porous than traditional solid sorbents, with surface areas ranging from 1,000 to 10,000 m2/g, exceeding the functionality of materials such as carbons and zeolites. This allows a warfighter’s uniform to trap chemical agents and offer the same protection as current chem-bio suits, with a significant reduction in bulk, heat and weight. The new MOFs, coined UiO-66-NH2, also have the added benefit of accelerating the destruction of nerve agents.

Selected MOFs must contain the necessary physical and chemical properties to neutralize nerve agents. For example, properties such as chemical and thermal stability are mportant to ensure the MOFs maintain their structural integrity while in use. UiO-66-NH2 has shown great stability and substantial reactivity towards both nerve and blister agents.

To incorporate these new materials into fabrics used in warfighters’ uniforms, North Carolina State University is using a technique called “atomic layer deposition,” which puts a thin layer of metal over nanofibers. This creates stability and provides a suitable environment to grow MOFs. The 2016 Angewante Chemie article, “Ultra-Fast Degradation of Chemical Warfare Agents using MOF -Nanofiber Kebabs,” demonstrated that UiO-66-NH2 can be coated to fibers and still maintain substantial reactivity towards the nerve agent soman, with a half-life on the order of minutes.

This new material with superior capabilities will allow a warfighters’ uniform to offer protection from CWAs without the need of a bulky protective suit. In an environment where every second counts, having built-in protection, without the thermal burden, could make all the difference.

POC: Ms. Tracee Whitfield; [e-mail]

• Date Taken: 04.04.2017
• Date Posted: 04.05.2017 10:21
• Story ID: 229236
• Location: FORT BELVOIR, VA, US