SAIP2014

Nitrogen dioxide and Ammonia Gas Sensing by Tungsten Trioxide Film

8 Jul 2014, 14:20

20m

D Les 201

Oral Presentation Track A - Division for Physics of Condensed Matter and Materials DPCMM1

Speaker

Mr Malcolm Govender (CSIR)

Apply to be<br> considered for a student <br> &nbsp; award (Yes / No)?

Yes

Would you like to <br> submit a short paper <br> for the Conference <br> Proceedings (Yes / No)?

No

Abstract content <br> &nbsp; (Max 300 words)<br><a href="http://events.saip.org.za/getFile.py/access?resId=0&materialId=0&confId=34" target="_blank">Formatting &<br>Special chars</a>

Tungsten oxide film was reactively-sputtered on alumina substrate with Pt-contacts from a pure W target and argon/oxygen-plasma. The synthesized and annealed tungsten oxide was characterized with XRD, XPS, Raman spectroscopy, UV/Vis spectroscopy and Resistance as a function of Temperature, and found to be stoichiometric triclinic phase tungsten trioxide. The pure film was used to sense ppm concentrations of nitrogen dioxide and ammonia at room-temperature and 100^oC. At 100^oC, The sensitivity of the film towards nitrogen dioxide increased, and decreased significantly towards ammonia. This was due to tungsten trioxide being an n-type metal-oxide semiconductor which preferred the reaction with the oxidizing gas over the reducing gas.

Main supervisor (name and email)<br>and his / her institution

Dr. Bonex W. Mwakikunga
BMwakikunga@csir.co.za

Level for award<br>&nbsp;(Hons, MSc, <br> &nbsp; PhD)?

PhD