Sensitivity enhancement of fiber surface plasmon resonance (SPR) sensor based upon a gold film-hexagonal boron nitride—molybdenum disulfide structure

Abstract

A new gold film-molybdenum disulfide (MoS2)-hexagonal boron nitride (h-BN) three-layer sensing structure is reported for sensing applications. The strong photoelectric conversion of MoS2 and the wide forbidden band of h-BN are used to enhance the surface plasmon resonance of the gold film which greatly enhance the sensitivity of the sensor. The Au film was deposited on the optical fiber by controlled vacuum sputtering to monitor the thickness. The MoS2 nanolayer was deposited on the surface of the gold film by electrostatic adsorption and the hexagonal boron nitride nanolayer was subsequently superimposed to complete the preparation. The sensitivity of the prepared sensor was increased to 3803.0 nm/RIU, which is 71.5% higher than for the common gold film sensor. These results confirmed that this approach significantly upgraded the sensor performance. The newly proposed SPR sensor performed well using a simple structure, is low-cost, offers high accuracy and favorable specificity, and may be used for small molecule detection for medical applications.