Not every object is food to a Venus flytrap. Like the carnivorous plant, a new material developed at Northwestern University permanently traps only its desired prey, the radioactive ion cesium, and not other harmless ions like sodium.
The synthetic material, made from layers of a gallium, sulfur and antimony compound, is very selective. The Northwestern researchers found it to be extremely successful in removing cesium — found in nuclear waste but very difficult to clean up — from a sodium-heavy solution. (The solution had concentrations similar to those in real liquid nuclear waste.)
It is, in fact, cesium itself that triggers a structural change in the material, causing it to snap shut its pores, or windows, and trap the cesium ions within. The material sequesters 100 percent of the cesium ions from the solution while at the same time ignoring all the sodium ions.
The results are published online by the journal Nature Chemistry.