• Fulltext


        Click here to view fulltext PDF

      Permanent link:

    • Keywords


      Li-ZnO; field-emission scanning electron microscopy; gas sensor; XPS; NO$_2$; crystal defect.

    • Abstract


      In this study, we explore the influence of Li dopant on the morphological, electrical and structural properties of ZnO thin films employed for gas-sensing applications. The deposited thin-film gas sensors were evaluated using X-ray diffraction, field-emission scanning electron microscopy, X-ray photoelectron spectroscopy (XPS), and Hall measurements to assess the chemical and physical features of Li-ZnO thin-film gas sensors. All films are crystallized with hcpstructure confirmed from X-ray diffraction analysis. From field-emission scanning electron microscopy analysis, spherical and uneven distribution of particles is observed in all the thin-film samples. The conductivity of the thin-film gas sensorsobtained from the Hall-measurement system shows that all samples except 5wt%Li-ZnO exhibit n-type conductivity. XPS studies confirmed the presence of defect states in all deposited samples. Enhanced nitrogen dioxide (NO$_2$) gas-sensing properties by incorporating an alkali metal (Li, 1–10 wt%) in ZnO were explored. Gas sensing measurements reveal that 1wt% Li-ZnO thin films exhibit remarkable sensitivity (20.94) and fast response/recovery (3s/112s) time towards 45 ppm of NO$_2$ gas. The results are discussed with the influence of defect density states in ZnO and correlated with structural, morphological and electrical parameters.

    • Author Affiliations



      1. Department of Physics, St. Thomas’ College (Autonomous), Thrissur 680001, India
      2. Department of Instrumentation, Cochin University of Science and Technology, Cochin 682022, India
      3. Centre for Materials for Electronics Technology (C-MET), Thrissur 680581, India
    • Dates

  • Bulletin of Materials Science | News

    • Dr Shanti Swarup Bhatnagar for Science and Technology

      Posted on October 12, 2020

      Prof. Subi Jacob George — Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bengaluru
      Chemical Sciences 2020

      Prof. Surajit Dhara — School of Physics, University of Hyderabad, Hyderabad
      Physical Sciences 2020

    • Editorial Note on Continuous Article Publication

      Posted on July 25, 2019

      Click here for Editorial Note on CAP Mode

© 2022-2023 Indian Academy of Sciences, Bengaluru.