H2 sensing performance of optical fiber coated with nano-platelet WO3 film

• Main Authors: Ou, Jian Zhen, Yaacob, Mohd. Hanif, Campbell, Jos Laurie, Breedon, Michael, Kalantar-zadeh, Kourosh, Wlodarski, Wojtek
• Format: Article
• Language: English
• Published: Elsevier 2012
• Online Access: http://psasir.upm.edu.my/id/eprint/48094/1/H2%20sensing%20performance%20of%20optical%20fiber%20coated%20with%20nano-platelet%20WO3%20film.pdf; http://psasir.upm.edu.my/id/eprint/48094/; http://www.sciencedirect.com/science/article/pii/S0925400511000505
• Institution: Universiti Putra Malaysia

For the first time, we have integrated nano-platelet Pd/WO3 films, which are formed using an acid etching method, with optical fibers to develop a hydrogen gas (H2) sensors. The tungsten films were firstly RF sputtered on top of optical fiber tips, and subsequently etched in 1.5 M nitric acid to produce tungstite films. After annealing at 300 and 480 °C, these films were coated with approximately 25 Å thick Pd layers. The films were characterized using SEM, GADDS, EDX, and both Raman and UV–vis–NIR spectroscopy. H2 testing measurements were conducted when the sensors were interacting with 0.06–1% H2 in synthetic air at an optimum temperature of 100 °C. It was found that the highly crystalline nano-platelet Pd/WO3 film based optical fiber H2 sensors show large reflectance responses in the NIR wavelength of 6% and 12% in the presence of 0.06% and 1% H2, respectively.