Ammonia Gas Detection Using an Optically Sensitive Hybrid Organic-Inorganic Multilayer Nanoporous Film

摘要

In this work, a highly porous nano-thin film composed of poly(diallyldimethylammonium chloride) and silica nanoparticles (SiO_2 NPs) was prepared on quartz plate using the layer-by-layer (LbL) method. Subsequently, a functional porphyrin compound, tetrakis-(4-sulfophenyl)porphine (TSPP), was infused into the porous film. Exposure of the film to ammonia induced spectral changes in the absorption spectrum of TSPP, indicating that the aggregation state of TSPP was changed from J-aggregation to monomeric or H-aggregation. Moreover, the TSPP infused porous film showed a correspording sensitivity in the concentration range of 10-100 ppm ammonia, showing a limit of detection (LOD) of ca. 1 ppm.