Fiber optic surface plasmon resonance based hexachlorobenzene sensor exploiting layer-by-layer coatings of GNP/SnO2 dendrites nanocomposite

An efficient fiber optic surface plasmon resonance based hexachlorobenzene (HCB) sensor is designed using layer by layer coating method. SnO2 nanoparticle [(SnO2)N] and SnO2 dendrites [(SnO2)D] are used to synthesize graphene nanoplatelets (GNP) based nanocomposites (labelled as GSN and GSD, respectively) to fabricate potential sensing layer. The combination of GNP and SnO2 nanostructures shows synergistic effects and provides high sensitivity and selectivity to the sensor. Post-immobilization method is used to prepare nanocomposites. Owing to difference in structures, GSN and GSD possess unique properties such as large surface area, catalytic nature, tunable porosity and non-toxicity and hence provide potential pathway for efficient sensing performance for HCB. Scanning electron microscopy (SEM) is used to confirm the preparation of [(SnO2)N], [(SnO2)D] and GSD. The GSD based probe fabricated with optimized parameters operates in the concentration range 0 g l−1 to 10−2 g l−1 with low detection limit 1.085 × 10−15 g l−1. The selectivity of the sensor is confirmed by carrying out the experiments using various possible interferands. The sensor can be used for online monitoring and remote sensing.