Refractory Coated Silica Aerogels ? Catchers for the Fast Release of Unstable Light Nuclei

Short-lived isotopes are expected to play a key role in unraveling the unanswered questions in nuclear physics, nuclear astrophysics and fundamental interactions at low energies. The Facility for Rare Isotope Beams under consideration for construction in the U.S., will have unique capabilities to develop exotic beams to facilitate these studies. The DOE-FRIB program is seeking advances in production techniques and improved yields of rare isotopes to overcome the limitations of existing Isotope Separation On-Line ,ISOL, techniques. This project will develop and test ISOL catchers based on aerogel nanotechnology. Silica aerogels with interconnected pores of different sizes have been developed and coated with refractory metal, tungsten, to achieve a density of 3.52 g per cc. The aerogels were structurally stable with open pores when heated to approximately 1300 degrees C. Phase I studies indicated the potential for further optimization and testing in Phase II. The Phase II project will develop the catcher materials from silica and zirconia aerogels and other nanoporous refractory materials. Internal pores of the silica aerogels will be coated with tungsten by atomic layer deposition. The nanoporous refractory materials will be evaluated at high temperatures up to 2000 degrees C. Promising catcher materials will be tested at a radioactive beam line facility for their ability to trap and release radioactive isotopes of alkalis and noble gases. Commercial Applications and other Benefits as described by the awardee: In addition to nuclear physics research, metal and metal oxide coated aerogels will have applications in catalysis, nano-photovoltaics, and in environmental decontamination, insulation, fuel storage, and in capacitors for energy storage.