An H₂S Gas Sensor Based on Long Period Gratings-Mach Zehnder Interferometer

This work presents a hydrogen sulfide (H2S) gas sensor manufactured using a Long Period Gratings-Mach Zehnder (LPG-MZ) interferometer that was coated with CuO nanoparticles. The LPG-MZ was fabricated using the electric-arc discharge method, and the resulting sensor was coated with CuO nanoparticles. Prior to testing with H2S, the sensor was characterized with aqueous solutions of varying refractive indices (RI), with a sensitivity of 186 nm/RIU between 1.35 and 1.39. The sensor was then tested with H2S concentrations ranging from 0 to 40 ppm and exhibited a sensitivity of approximately 7.8 pm/ppm between 5 and 20 ppm.