Detecting Binary Mixtures of Sulfolane with Ethylene Glycol, Diethylene Glycol, and Polyethylene Glycol in Water Using Surface Plasmon Resonance Sensor: A Numerical Investigation

This work offers a quite sensitive SPR-based sensor with a new heterostructure based on platinum and ITO using silver as the plasmonic metal to examine the detection of sulfolane, ethylene glycol, diethylene glycol, and polyethylene glycol (PEG-200 and PEG-600) in water. The widely utilized transfer matrix technique (TMM) was employed to evaluate the performance of the suggested sensor. The noble plasmonic material silver (Ag) with a thickness of 40 nm is utilized to induce surface plasmons. As an adhesive layer, Cytop is used between the ITO and sensing layer; the thickness of 0.5 nm has been taken. The sensor’s performance was evaluated in terms of reflectance, full width at half maximum (FWHM), detection accuracy, sensitivity, and figure of merit. These parameters are also evaluated by varying the platinum (P) and ITO (I) layers. The suggested sensor has a maximum sensitivity of 144.1988 degree/RIU (for P=1, I=9 ), DA of 1.8867 degree −1 , and FoM of 98.66 RIU −1 (for P=3, I=1 ). The operating wavelength of 633 nm is used here for this numerical analysis.