H₂S Sensing Properties of Added Copper Oxide in WO₃

Abstract:

We study Hydrogen sulfide gas detection properties of pure and 1% copper oxide added WO₃ thin films. The spin coated deposits on alumina substrates were annealed at 500 C for 1 hour in order to improve the crystallinity of the films. The sensitivity of pure tungsten oxide is poor even at temperatures of about 100 C but the doped samples exhibit good response to H₂S gas. Our data show sensitivity of about 1500 in 10 ppm diluted gas in air at 100 C. The films are sensitive to the gas even at 250 ppb (sensitivity about 2) H₂S concentration at 100 C but with rather long recovery time. Crystal structure, morphology and chemical composition of samples were studied by X-Ray diffraction (XRD), scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) analyses. We suggest that Cu₂O dopants dissociate H₂S molecules and spillover of the hydrogen atoms onto the cracked WO₃ surface. The reaction of dissociated H₂S with adsorbed oxygen is the main reason for reduction of resistivity.

• Periodical: Key Engineering Materials (Volume 543)
• Pages: 145-149
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.543.145
• Online since: March 2013
• Authors: Rasoul Nowrouzi, Fatemeh Razi Astaraei, Shima Kashani, Azam Iraji Zad
• Keywords: Catalytic Additives, Copper Oxide, H₂S Sensor, WO₃

References

[1] X. Li, Y. Wang, Y. Lei, and Z. Gu, RSC Advances, 2 (2012), 2302-07.

[2] S. Pandey, K. Kim, and K. Tang, TrAC Trends in Analytical Chemistry, 32 (2012), 87-99.

[3] D. Vuong, G. Sakai, K. Shimanoe, and N. Yamazoe, Sensors and Actuators B: Chemical, 105 (2005), 437-42.

[4] E. Barrett, G. Georgiades, and P. Sermon, Sensors and Actuators B: Chemical, 1 (1990), 116-20.

[5] J. Solis, S. Saukko, L. Kish, C. Granqvist, and V. Lantto, Thin Solid Films, 391 (2001), 255-60.

DOI: 10.1016/s0040-6090(01)00991-9

[6] Z. Liu, T. Fan, D. Zhang, X. Gong, and J. Xu, Sensors and Actuators B: Chemical, 136 (2009), 499-509.

[7] V. Kapse, S. Ghosh, G. Chaudhari, and F. Raghuwanshi, Talanta, 76 (2008), 610-16.

[8] N. Ramgir, S. Ganapathi, M. Kaur, N. Datta, K. Muthe, D. Aswal, S. Gupta, and J. Yakhmi, Sensors and Actuators B: Chemical, 151 (2010), 90-96.

DOI: 10.1016/j.snb.2010.09.043

[9] S. Gentry, and T. Jones, Sensors and Actuators, 10 (1986), 141-63.

[10] A. Chowdhuri, V. Gupta, K. Sreenivas, R. Kumar, S. Mozumdar, and P. Patanjali, Applied Physics Letters, 84 (2004), 1180-82.

DOI: 10.1063/1.1646760

[11] H-M. Lin, C-M. Hsu, H-Y. Yang, P-Y. Lee, and C-C. Yang, Sensors and Actuators B: Chemical, 22 (1994), 63-68.

[12] E. Comini, AnalyticaChimicaActa, 568 (2006), 28-40.

[13] L. Reyes, A. Hoel, S. Saukko, P. Heszler, V. Lantto, and C. Granqvist, Sensors and Actuators B: Chemical, 117 (2006), 128-34.

DOI: 10.1016/j.snb.2005.11.008