Investigations on SPR induced Cu@Ag core shell doped SiO2-TiO2-ZrO2 fiber optic sensor for mercury detection

•The present work proposes a simple and low cost method for mercury sensing based on fiber optic sensor.•This fiber optic sensor is made up of Cu@Ag core-shell nanoparticles doped in SiO2-TiO2-ZrO2 ternary matrix.•The sensor is found to have a very low detection limit of 0.01 µM and a broad range of 0.01–1000 µM.•A simple, economical and reproducible mercury sensor with good repeatability is successfully produced. An investigation on Surface Plasmon Resonance (SPR) based fiber optic sensor for mercury detection utilizing copper-silver core shell nanoparticles (Cu@Ag CNPs) was carried out. TEM analysis was used to confirm the formation and morphological characteristics of the CNPs, whereas EDS and AAS analysis were used to validate the successful formation of the core shell nanoparticles. Good selectivity and sensitivity towards mercury were established by means of UV–Vis absorption spectroscopy. SPR based fiber optic mercury sensor was fabricated using Cu@Ag CNPs as the sensing materials and the results clearly prove that the Cu@Ag CNPs can act as suitable candidates for the same.