Room-temperature semiconductor gas sensor based on nonstoichiometric tungsten oxide nanorod film

Yong Shin Kim; Ha, Seung-Chul; Kim, Kyuwon; Yang, Haesik; Choi, Sung-Yool; Kim, Youn Tae; Park, Joon T.; Lee, Chang Hoon; Choi, Jiyoung; Paek, Jungsun; Lee, Kwangyeol
May 2005
Applied Physics Letters;5/23/2005, Vol. 86 Issue 21, p213105
Academic Journal
Porous tungsten oxide films were deposited onto a sensor substrate with a Si bulk-micromachined hotplate, by drop-coating isopropyl alcohol solution of highly crystalline tungsten oxide (WO2.72) nanorods with average 75 nm length and 4 nm diameter. The temperature-dependent gas sensing characteristics of the films have been investigated over the mild temperature range from 20 to 250 °C. While the sensing responses for ammonia vapor showed increase in electrical conductivity at temperatures above 150 °C as expected for n-type metal oxide sensors, they exhibited the opposite behavior of unusual conductivity decrease below 100 °C. Superb sensing ability of the sensors at room temperature in conjunction with their anomalous conductivity behavior might be attributed to unique nanostructural features of very thin, nonstoichiometric WO2.72.


Related Articles

  • Properties of tungsten oxide thin films formed by ion-plasma and laser deposition methods for MOSiC-based hydrogen sensors. Fominski, V.; Grigoriev, S.; Romanov, R.; Zuev, V.; Grigoriev, V. // Semiconductors;Mar2012, Vol. 46 Issue 3, p401 

    Thin-film structures based on gas-sensitive tungsten oxide and catalytic platinum are fabricated by room-temperature deposition on a silicon carbide wafer using pulsed laser and ion-plasma methods. Oxide layer annealing in air to 600°C caused the formation of microstructured and...

  • Zinc-oxide thin-film ammonia gas sensors with high sensitivity and excellent selectivity. Nanto, Hidehito; Minami, Tadatsugu; Takata, Shinzo // Journal of Applied Physics;7/15/1986, Vol. 60 Issue 2, p482 

    Presents information on a study which prepared a sensor with a high sensitivity and an excellent selectivity for ammonia gas by using sputtered zinc oxide thin films. Response of the sensor to ammonia gas; Methodology of the study; Results and discussion.

  • Design of Optical Fiber Hydrogen Sensor Based on Platinum-Doped Tungsten Trioxide Films. ZELUN LI; CHUANDE ZHOU; XIANLING DENG; YIKE TANG // Asian Journal of Chemistry;2014, Vol. 26 Issue 17, p5717 

    Tungsten oxide (WO3) is applied extensively because of its electrochromic, photochromic and gasochromic properties. In this work, a type of optical fiber hydrogen (H2) sensor based on platinum-doped WO3 films was designed. The preparation and hydrogen sensing properties of platinum-doped WO3...

  • Tin Modified Tungsten Oxide Thin Film for Ammonia Gas Sensing at Room Temperature. Patel, K. J.; Desai, M. S.; Panchal, C. J. // Sensors & Transducers (1726-5479);Aug2012, Vol. 143 Issue 8, p136 

    Tin (Sn) modified Tungsten oxide (WO3) thin film gas sensor was prepared on glass substrate having Aluminum (Al) interdigitated electrode by thermal evaporation for detecting Ammonia (NH3) gas. The Sn concentration is changed by changing the thickness of the Sn film on WO3 and subsequently...

  • Electrochromic mechanism in a-WO[sub 3-y] thin films. Se-Hee Lee; Cheong, Hyeonsik M. // Applied Physics Letters;1/11/1999, Vol. 74 Issue 2, p242 

    Studies the electrochromic mechanism in amorphous tungsten oxide thin films using Raman scattering measurements. Characteristics of the Raman spectra of as-deposited films; Extra Raman peaks caused by insertion of lithium or hydrogen ions and electrons.

  • Properties of Hydrogen Sulfide Sensors Based on Thin Films of Tin Dioxide and Tungsten Trioxide. Sevastianov, E.; Maksimova, N.; Chernikov, E.; Sergeichenko, N.; Rudov, F. // Russian Physics Journal;Dec2016, Vol. 59 Issue 8, p1198 

    The effect of hydrogen sulfide in the concentration range of 0-100 ppm on the characteristics of thin films of tin dioxide and tungsten trioxide obtained by the methods of magnetron deposition and modified with gold in the bulk and on the surface is studied. The impurities of antimony and nickel...

  • Preparation and Assessment of Thin Films for Use as Ammonia Sensors. Lacy, Fred // Proceedings of the World Congress on Engineering & Computer Scie;2013, p1 

    Sensors are becoming increasingly more important as evidenced by their use in such diverse fields as agriculture, military, medicine, electronics, aerospace engineering, automobile industries, environmental protection, homeland security, as well as factory process monitoring. Research is...

  • Gas-Sensing Devices Based on Zn-Doped NiO Two-Dimensional Grainy Films with Fast Response and Recovery for Ammonia Molecule Detection. Wang, Jian; Wei, Xiaowei; Wangyang, Peihua // Nanoscale Research Letters;12/2/2015, Vol. 10 Issue 1, p1 

    Zn-doped NiO two-dimensional grainy films on glass substrates are shown to be an ammonia-sensing material with excellent comprehensive performance, which could real-time detect and monitor ammonia (NH) in the surrounding environment. The morphology and structure analysis indicated that the...

  • Flash evaporated tungsten oxide thin films for electrochromic applications. Losier, P.; Ashrit, P. V. // Journal of Materials Science Letters;Aug2003, Vol. 22 Issue 15, p1095 

    Examines the optical and electrochromic performance of flash evaporated tungsten oxide thin films. Effect of flash evaporation on the film formation kinetics and in nanostructuring the film; Suggestion that the overall transmission of the film decreases rather drastically due to broadband...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics