FORMATION AND STRUCTURE OF A TIN-IRON OXIDE SOLID-STATE SYSTEM WITH POTENTIAL APPLICATIONS IN CARBON-MONOXIDE SENSING THROUGH THE USE OF CYANOGEL CHEMISTRY

The reaction of aqueous solutions of SnCl4 . 5H(2)O and K4Fe(CN)(6) in a 2/1 Sn/Fe atomic ratio results in a hydrogelled polymeric material, characterized by bridging cyanides between the central metals of the adducts. Materials of this type have previously been noted upon reacti on of PdCl42- with cyanometalates in aqueous solution and have been re ferred to as cyanogels. Dehydration of Sn/Fe cyanogels results in xero gels that maintain the initial polymeric structure of the hydrogel. Th ermal processing of such gels under an air atmosphere at 900 degrees C produces a solid homogeneous mixture of microcrystalline SnO2 and Fe2 O3.