Single-atom-catalyst membranes for chem/bio protection

Project Overview

Heterogeneous single-atom catalysts incorporated into metal-organic frameworks (MOFs) have shown great promise for rapid chemical agent degradation. Essentially all work so far focused on demonstrating coated fibers and porous adsorbents in powder form. Little attention has been given to the formation of thin selective membranes from single-atom catalysts, yet materials of this type could enable a new paradigm of protection by combining rapid catalytic degradation with size sieving into a single, breathable layer.

This study provides a proof-of-concept demonstration of an easily scalable, ultrathin, breathable membrane made of covalently bonded, customizable single-atom catalytic monomers (nitrogen-based macrocycles coordinating a metal center) for personnel protection against chemical/biological agents. We show that the nanometer-sized pores of these membranes block penetration of biological threats, and the intrinsic catalytic activity decomposes organophosphates upon contact, thus reducing risk of secondary chemical agent exposure and enabling regeneration for extended use. The membrane is fabricated by interfacial polymerization (IP), a highly scalable method. Because of their high porosity and thinness, the membranes display high breathability. Ultrathin catalytic membranes of this type are expected to improve wearer safety and extend comfortable operation in contaminated environments for the military, medical, and civilian personnel.

Mission Impact

This foundational work boosts Lawrence Livermore National Laboratory (LLNL) unique competency in multifunctional materials science and technology (S&T) for defense and public health applications and, more broadly, competitiveness in the chem/bio security area. The goals of this project are strongly aligned with Bioscience & Bioengineering ("design and engineer nanostructured materials for national security applications") and Accelerated Materials & Manufacturing Core Competencies ("meet national need for rapid, cost-effective development of advanced materials and manufacturing"), as well as the Threat Preparedness and Response Mission area ("developing innovating approaches to threat neutralization and defeat"). In addition, the demonstrated multifunctional material class offers a new tool for unencumbering the warfighters, a key priority for Department of Defense Science and Technology.