Ultrahigh Sensitivity Surface Plasmon Resonance-Based Fiber-Optic Sensors Using Metal-Graphene Layers with Ti3C2Tx MXene Overlayers

Precise detection of volatile organic compounds (VOCs) using high-sensitivity fiber-optic probes is highly desirable for rapid screening in the fields of medicine and food processing. A novel spectral surface plasmon resonance (SPR)-based fiber-optic sensor incorporating metal/graphene/Ti(3)C(2)T(x )MXene layers for the detection of VOCs such as acetone and ethanol is proposed in this study. For the detection of acetone, optimum sensitivities of 5150, 4500, and 4200 nm/refractive index unit (RIU) are obtained using simulations, for sensors with Au, Ag, and Al, respectively, as metal layer. The highest sensitivity achieved at reasonably good detection accuracy is 19,750 nm/RIU, using a Au/graphene/Ti3C2Tx sensor, for VOCs with refractive index 1.434. Graphical