Second Generation Nanostructured Metal Oxide Matrices to Increase the Thermal Stability of CO and NO₂ Sensing Layers Based on Iron(II) Phthalocyanine

Abstract

Abstract An iron(II) phthalocyanine (FePc) complex solubilized by decylamine (DA) and benzylamine (BA) is incorporated into a nanoparticulate metal oxide matrix to develop optical sensor films sensitive to NO 2 and CO. Eleven amine solvents have been tested as N ‐donor ligands that permit ligand exchange with the gas molecules. We have systematically investigated the suitability of different N ‐donor ligands, studied the thermal stability of the NO 2 ‐ and CO‐sensing films at 4, 25, 60, and 80 °C by photometry, and corroborated our findings by using NMR experiments. A satisfactory thermal stability of the films has not been obtained for chemically unmodified nanoparticulate metal oxide matrices. We have therefore developed a second generation of nanostructured metal oxide supports that show increased thermal stability and adequate sensitivity to NO 2 and CO. These novel nanostructured matrices have been chemically modified using amines, alumina oligomers, and/or anti‐gas‐fading agents. These components have been integrated into the metal oxide matrices to avoid degradation of the optical films and to preserve their sensitivity.