Nitrogen Oxide Adsorption Property of A_xFe_xSn_8-xO₁₆ Hollandite (A: K, Rb, Cs)

Abstract

Hollandite-type A_xFe_xSn_8-xO₁₆ (A: K, Rb, Cs) powder were prepared by conventional solid state reaction method for studying the correlation of nitrogen oxide (NO) adsorption mechanism on its surface. Observation of NO adsorption was performed by the diffuse reflectance infrared fourier transformed spectroscopy (DRIFTS). After adsorbed NO gas on hollandite surface, absorption bands around 1350–1400 cm⁻¹ and 1750 cm⁻¹ were observed as KNO₃. And, NO adsorption of A_xFe_xSn_8-xO₁₆ surface was observed until 400°C, respectively. From the NO adsorption property on hollandite surface by DRIFT spectra, it was found that the presence of oxygen in carrier gas had a significant contribution for NO adsorption, and the active point was alkaline metal ions located at the end of one-dimensional tunnel.