Polyoxometalate-based gasochromic silica

Abstract

Materials capable of gasochromic behavior are still rare. In this paper, amorphous gasochromic hybrid silica material containing phosphomolybdic acid (PMo₁₂) is prepared by the sol–gel technique. The structure and properties of the material are investigated by cyclic voltammetry, thermal gravimetric analysis, FT-IR spectra, X-ray diffraction, UV-Vis spectra and X-ray photoelectron spectra. The structural integrity of phosphomolybdic acid has been preserved after incorporation into the porous silica framework. Furthermore, the PMo₁₂–SiO₂ hybrid material shows sensing activity for H₂S and SO₂ gases at room temperature based on the color change.