Authors

Fatemeh Tavakoli Foroushani, Hossein Tavanai, Mehdi Ranjbar, Hajir Bahrami

Publication date

2018/9/1

Journal

Sensors and Actuators B: Chemical

Volume

268

Pages

319-327

Publisher

Elsevier

Description

The application of tungsten oxide nanofibers for gasochromic hydrogen sensing is reported. Three tungsten oxide nanofibrous webs were fabricated by electrospinning proxopolyltungestic acid incorporated in polyvinylpyrrolidone. The samples were then calcinated to remove Polyvinylpyrrolidone to obtain tungsten oxide nanofibers. The tungsten oxide nanofiber samples had a grain form with an average fiber diameter of 103 nm, 181 nm and 293 nm. The tungsten oxide nanofibrous webs showed a very good sensitivity to concentartions of hydrogen (in argon) as low as 2% at room temperature. This is very important as the electrical hydrogen gas sensors need high temperatures to sense hydrogen. Upon contacting hydrogen, the almost colorless nanofibers turn into blue in less than 2 min. Cyclic hydrogen – oxygen exposure showed that the samples could be reused after two cycles. XRD, Raman and FTIR …