A novel method of SPR based SnO₂: GNP nano-hybrid decorated optical fiber platform for hexachlorobenzene sensing

A novel fiber optic hexachlorobenzene (HCB) sensor is designed using nano-hybrid of graphene nanoplatelets (GNP) supported with tin oxide (SnO₂) nanoparticles based on surface plasmon resonance (SPR). In the nano-hybrid, pre-synthesized SnO₂nanoparticles are decorated on GNP and combined effects of both are used to enhance the chemical reactivity for HCB detection. GNP/SnO₂ nano-hybrid owing to its synergistic properties such as high conductivity, surface area, reactivity, and catalytic behaviour promises excellent sensitivity and selectivity to sense HCB. With optimized parameters, the proposed probe achieves good sensing performance to detect HCB concentration in a wide range from 0 g/L to 10⁻² g/L. A red shift of 74 nm in peak absorbance wavelength is observed for this concentration range. The sensor possesses 8.67 × 10⁻¹³ g/L as the limit of detection which is smaller than the values reported in the literature for sensors utilizing various other techniques. Further, the HCB concentration in real samples is tested using proposed probe and the results are found to be close to the values reported in the literature. In addition, the interference of other analytes on the performance of the sensor is reported. The sensor can be used for online monitoring and remote sensing.