Materials for capture, release, and separation of iodine and other halogens

Researchers in Prof. Hemamala Karunadasa's laboratory have developed inexpensive, robust, high capacity hybrid materials for reversible or irreversible capture of halogens (chlorine, bromine, and iodine gas). These non-porous organic-inorganic layered solids have high gravimetric and volumetric storage capacity. Further, they can be tuned for timed release to enable transportation of the halogen and to easily regenerate the capture material. They can also purify gases by separating different halogens. Iodine capture applications of this technology include sequestration and transportation of radioactive iodine from nuclear fuel streams; chemical purification; and solid-state antimicrobial materials for disinfection of surfaces and environment (for example, in air filters).

X-ray structures of iodine capture material: a before capture and b its reaction product with iodine. Insets show the individual cations in the organic layers. (Orange, purple, brown, blue, and grey spheres represent Pb, I, Br, N, and C atoms, respectively.)

Stage of Research
The inventors have created the materials as microcrystalline powder and oriented thin films. These materials have demonstrated gravimetric capacities up to 43% for iodine capture; tunable half-life for iodine release; and resistance to HCl, water, and NOx gases. The inventors continue to explore synthesis of nanoparticles and coating filters.