Skip to content
University of Maryland LibrariesDigital Repository at the University of Maryland
    • ログイン
    アイテム表示 
    •   ホーム
    • Theses and Dissertations from UMD
    • UMD Theses and Dissertations
    • アイテム表示
    •   ホーム
    • Theses and Dissertations from UMD
    • UMD Theses and Dissertations
    • アイテム表示
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    Synthesis and integration of one-dimensional nanostructures for chemical gas sensing applications

    Thumbnail
    閲覧/開く
    umi-umd-4372.pdf (16.35Mb)
    No. of downloads: 1100

    日付
    2007-04-30
    著者
    Parthangal, Prahalad Madhavan
    Advisor
    Zachariah, Michael R
    Metadata
    アイテムの詳細レコードを表示する
    抄録
    The need for improved measurement technology for the detection and monitoring of gases has increased tremendously for maintenance of domestic and industrial health and safety, environmental surveys, national security, food-processing, medical diagnostics and various other industrial applications. Among the several varieties of gas sensors available in the market, solid-state sensors are the most popular owing to their excellent sensitivity, ruggedness, versatility and low cost. Semiconducting metal oxides such as tin oxide (SnO2), zinc oxide (ZnO), and tungsten oxide (WO3) are routinely employed as active materials in these sensors. Since their performance is directly linked to the exposed surface area of the sensing material, one-dimensional nanostructures possessing very high surface to volume ratios are attractive candidates for designing the next generation of sensors. Such nano-sensors also enable miniaturization thereby reducing power consumption. The key to achieve success in one-dimensional nanotechnologies lies in assembly. While synthesis techniques and capabilities continue to expand rapidly, progress in controlled assembly has been sluggish due to numerous technical challenges. In this doctoral thesis work, synthesis and characterization of various one-dimensional nanostructures including nanotubes of SnO2, and nanowires of WO3 and ZnO, as well as their direct integration into miniature sensor platforms called microhotplates have been demonstrated. The key highlights of this research include devising elegant strategies for growing metal oxide nanotubes using carbon nanotubes as templates, substantially reducing process temperatures to enable growth of WO3 nanowires on microhotplates, and successfully fabricating a ZnO nanowire array based sensor using a hybrid nanowire-nanoparticle assembly approach. In every process, the gas-sensing properties of one-dimensional nanostructures were observed to be far superior in comparison with thin films of the same material. Essentially, we have formulated simple processes for improving current thin film sensors as well as a means of incorporating nanostructures directly into miniature sensing devices. Apart from gas sensing applications, the approaches described in this work are suitable for designing future nanoelectronic devices such as gas-ionization, capacitive and calorimetric sensors, miniature sensor arrays for electronic nose applications, field emitters, as well as photonic devices such as nanoscale LEDs and lasers.
    URI
    http://hdl.handle.net/1903/6881
    Collections
    • Mechanical Engineering Theses and Dissertations
    • UMD Theses and Dissertations

    DRUM is brought to you by the University of Maryland Libraries
    University of Maryland, College Park, MD 20742-7011 (301)314-1328.
    Please send us your comments.
    Web Accessibility
     

     

    ブラウズ

    リポジトリ全体コミュニティ/コレクション公開日著者タイトル主題このコレクション公開日著者タイトル主題

    登録利用者

    ログイン登録
    Pages
    About DRUMAbout Download Statistics

    DRUM is brought to you by the University of Maryland Libraries
    University of Maryland, College Park, MD 20742-7011 (301)314-1328.
    Please send us your comments.
    Web Accessibility