High-sensitivity H<sub>2</sub>S gas sensor based on asymmetric modes in long-period fiber grating
A long-period fiber grating (LPFG) sensor coated with zinc oxide (ZnO) film is proposed for the detection of hydrogen sulfide (H<sub>2</sub>S), which is based on the combined high-response characteristics of asymmetric cladding modes and the sensitive film. The asymmetric cladding modes are excited by fabricating the grating in an asymmetric dual-core fiber (ADCF). By simulating the sensitivity of the ADCF-LPFG sensor with different thicknesses in the mode transition region, the optimal film thickness is determined to be 120 nm. Experimentally, the sensor achieves a maximum H<sub>2</sub>S concentration sensitivity of 63.21 pm/ppm in the range of 4.93-41.6 ppm. It also exhibits excellent stability of 0.0011% and a detection limit of 2.432 ppm. Additionally, the sensor demonstrates a temperature sensitivity of -83.17 pm/°C over the range of 10-40°C. The designed sensor features high sensitivity and compact structure, demonstrating significant potential for simultaneous detection of H<sub>2</sub>S concentration and temperature.
Authors
- Chuanlu Deng (ORCID: https://orcid.org/0009-0007-6497-2430)
- Jun Liao (ORCID: https://orcid.org/0000-0002-2677-8465)
- Yi Huang (ORCID: https://orcid.org/0000-0002-4381-6291)
- Qi Zhang (ORCID: https://orcid.org/0000-0001-8983-1246)
- Xiaobei Zhang (ORCID: https://orcid.org/0000-0002-9228-8720)
- Chengzhi Hu (ORCID: https://orcid.org/0000-0002-8627-2335)
- Wang Yun-xiang
- Yanhua Dong
- Tingyun Wang (ORCID: https://orcid.org/0000-0003-0579-2089)
- Feng Zhu (ORCID: https://orcid.org/0000-0001-8362-9768)
- Yingying He
Institutions
- Shanghai University (CN)
Publication Details
- Journal
- Optics Express
- Published
- 2025-09-04
- DOI
- https://doi.org/10.1364/oe.572641
- Primary Topic
- Advanced Fiber Optic Sensors
- Type
- article
- Field-Weighted Citation Impact
- 0.00