Metal Nanocomposites as Optical Sensor for Ions and Molecules of Environmental Concern

Abstract

Multi phasic metal nanocomposites comprising a zero-dimensional metal nanoparticles phase (0.5–5% w/w) have significantly enhanced the material property and sensing ability of easily recoverable conventional matrices like glass, ceramics, metal, carbon allotropes or polymers. Over the past few years, promising chemical and physical properties of metal nanocomposites, developed via direct in situ chemical, photocatalytic, or thermal reduction of metal salts, over common matrix, or ex situ direct insertion of nanoparticles into the polymer. Colorimetric MNC sensors like metal–metal oxide NPs, quantum dots have depicted a relation between their type, structure, function and sensing performance, via aggregation/decomposition of NPs, fluorescence on/off and ligand-receptor interaction. Functional single/multilayered transition-metal dichalcogenides have been employed both, as a matrix for their decoration exhibiting synergism and quite recently as nanocomposites exhibiting ultra-fast and selective multi-sensor activity over narrow detection limits that are an urgent demand of national, homeland and environment safety. Fabrication of these biosensors endorse their progress in environmental and material aspects. They are employed as bio-analytic sensors against excess of heavy metal ions, nitro-compounds, poly-aromatic hydrocarbons, microbial proteins etc. imparting exclusive photo-chromatic and electronic properties, tuned at grass-root level by adjusting various supramolecular interactions and also the metal-ligands interactions at molecular level. Nanocomposites have several applications mainly in biological arenas, solar cells, communication field, optoelectronic devices etc. In this chapter we would discuss about recently developed nanocomposite-sensors, their synthesis, mechanism for their sensing action and environmental application involving mainly optical sensors. © 2022, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.