Optimization of tapered microfiber humidity sensors with molybdenum disulfide coating

Abstract

This study focuses on developing and optimizing a new optical sensor using tapered microfiber (TMF) for humidity sensing in the 30-80% Relative Humidity (%RH) range. The TMF was fabricated with varying heating lengths (3-6 mm) and waist diameters (3-7 µm), and its performance was tested using a tunable light source and an optical power meter. Results showed that a 5 mm TMF with a 3 µm waist diameter provided the best stability and sensitivity for humidity sensing. Additionally, coating the TMF with Molybdenum Disulfide (MoS2) nanoflakes improved sensitivity by 20-50%, with an error margin of less than 5%. The optimized sensor achieved a sensitivity of -0.244 dB/% and over 97% linearity, demonstrating its potential for precise humidity detection in environmental applications.