LSPR-Based Optical Fiber Sensor Utilizing GO-ZnO Nanocomposite for Relative Humidity Measurement

This letter describes the development and characterization of a novel optical fiber relative humidity (RH) sensor leveraging Localized Surface Plasmon Resonance (LSPR). The sensor utilizes an in-house synthesized GO-ZnO nanocomposite (NC)-doped silica film coated on gold nanoparticle coated U-bend plastic-clad silica (PCS) fiber. It shows a linear response across a broad RH range of 15-90%, with a sensitivity of 0.1359 nm/%RH, and features rapid response and recovery times of 5s and 7s. The sensor’s response is fully reversible and repeatable.