MXene-based fibre optic Fabry-Perot interferometer for heavy metal detection

In this work, we propose a miniature and high-performance MXene-based fibre optic Fabry-Perot Interferometer (FPI) for the detection of heavy metal (mercury) in the water. Light from fibre tips (FP cavity) induce interference through partial reflection at interfaces. The systematic investigations have been conducted for the free spectral range against the FP cavity length, the effect of finesse on the surface reflectance of FP cavity surface using thin film gold-coated fibre tips of various thickness in nanometre scales. The FP fibre tip deposited with MXene nanolayer will be developed to detect Hg²⁺ in water by inducing a strong response through the adsorption and reduction of Hg²⁺ to Hg⁺ with MXene nanomaterials. The nanomaterial integrated FPI sensing scheme could be an alternative for food, water quality, and environmental monitoring.