Ultrashort Near-Infrared Fiber-Optic Sensors for Carbon Dioxide Detection

作者：Chong Xinyuan^*; Kim Ki Joong; Ohodnicki Paul R; Li Erwen; Chang Chih Hung; Wang Alan X

来源：IEEE Sensors Journal, 2015, 15(9): 5327-5332.

DOI：10.1109/JSEN.2015.2438063

• Fiber optic sensor
• gas sensor
• near infrared absorption
• metal-organic framework

In this paper, we report a fiber-optic carbon dioxide (CO2) near-infrared (IR) absorption sensor with only 8-cm sensing length that is coated with nanoporous metalorganic framework material Cu-BTC (BTC = benzene-1,3, 5-tricarboxylate). The multimode optical fiber was etched by hydrofluoric acid to remove the cladding and part of the core, resulting in larger evanescent field to sense the near-IR absorption induced by the adsorbed CO2. The Cu-BTC thin film with 100 nm thickness was then grown onto the ethced core through a stepwise layer-by-layer method. Our real-time measurement results show that the CO2 detection limit is better than 500 ppm and the overall response time is 40 s for absorption and 75 s for desorption. To the best of our knowledge, this is the shortest near-IR fiber-optic sensor for CO2 detection at 1.57-mu m wavelength.

• 出版日期2015-9