Spongy chalcogels of non-platinum metals act as effective hydrodesulfurization catalysts

Abstract

Aerogels are low-density porous materials, made mostly of air, for which hundreds of applications have been found in recent years. Inorganic oxide-based aerogels have been known for a long time, carbon aerogels were discovered in the early 1990s and sulfur- and selenium-based aerogels (chalcogels) are the most recent additions to this family. Here we present new aerogels made of Co(Ni)-Mo(W)-S networks with extremely large surface areas and porosity. These systems are formed by the coordinative reactions of (MoS(4))(2-) and (WS(4))(2-) with Co(2+) and Ni(2+) salts in non-aqueous solvents. We show that these low-density sponge-like networks can absorb conjugated organic molecules and mercury ions, and preferentially adsorb CO(2) over H(2), which illustrates their high potential as gas-separation media. The chalcogels are shown to be twice as active as the conventional sulfided Co-Mo/Al(2)O(3) catalyst for the hydrodesulfurization of thiophene.