Selective Adsorption of Volatile Hydrocarbons and Gases in High Surface Area Chalcogels Containing [ES₃]^3–Anions (E = As, Sb)

We describe the sol–gel synthesis of the two new chalcogels KFeSbS 3 and NaFeAsS 3, which demonstrate excellent adsorption selectivity for volatile hydrocarbons and gases. These predominantly mesoporous materials have been synthesized by reacting Fe(OAc) 2 with K 3 SbS 3 or Na 3 AsS 3 in a formamide/water mixture at room temperature. Aerogels obtained after supercritical drying have BET surface areas of 636 m 2 /g and 505 m 2 /g for KFeSbS 3 and NaFeAsS 3, respectively, with pore sizes in the micro- (below 2 nm), meso- (2–50 nm), and macro- (above 50 nm) regions.