Powders and films composed of tin dioxide (SnO2) are promising candidates for a variety of high-impact applications, and despite the material’s prevalence in such studies, it remains of high importance that commercially available materials meet the quality demands of the industries that these materials would most benefit. Imaging techniques, such as scanning electron microscopy (SEM), atomic force microscopy (AFM), were used in conjunction with Raman spectroscopy and X-ray photoelectron spectroscopy (XPS) to assess the quality of a variety of samples, such as powder and thin film on quartz with thicknesses of 41 nm, 78 nm, 97 nm, 373 nm, and 908 nm. In this study, the dependencies of the corresponding Raman, XPS, and SEM analysis results on properties of the samples, like the thickness and form (powder versus film) are determined. The outcomes achieved can be regarded as a guide for performing quality checks of such products, and as reference to evaluate commercially available samples.
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Synthesis, Spectroscopic Characterization and Applications of Tin Dioxide
Metal oxides are useful for the detection and sensing of combustible and
toxic gases, and for use in lithium batteries and solar cells. The present study focuses
on the spectroscopic investigation of commercial and in-house laboratory synthesized
tetragonal tin dioxide (SnO2), aimed at studying its physical and chemical properties
at nanoscale levels and in bulk. We have investigated the pure powder form and
thin films prepared on two different types of substrate, silicon and UV-Quartz, each
with five different thicknesses (i.e. 41, 78, 96.5, 373, and 908 nm). Raman spectroscopy
with two different laser excitation wavelengths, namely 780 and 532 nm,
has been used to investigate the various SnO2 vibrational modes. Thermal effects
on the primary vibrational features in the Raman spectra have been studied in the
range 30–170 °C. X-ray diffraction (XRD) spectra have been recorded to confirm the
rutile structure of tin dioxide and to obtain information on the spherical grain particle
size of SnO2 with EDS analysis for the thin film samples. Scanning Electron Microscope
(SEM) images have been recorded in order to understand the morphology of
the particles of SnO2 at the nanoscale level. In addition, FT-IR spectra have been
obtained to study the IR-active vibrational modes for the bulk and thin film samples
on the two substrates. Moreover, UV-VIS spectra have been employed to determine
the energy band gap for the SnO2 film samples by an efficient process facilitated by
a Tauc plot technique utilizing an in-house developed python script.
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- Award ID(s):
- 1659224
- NSF-PAR ID:
- 10209713
- Editor(s):
- Mubarak, Nabisab M.; Walvekar, Rashmi; Arshid, Numan; and Khalid, Mohammad
- Date Published:
- Journal Name:
- Chapter in Book: Contemporary Nanomaterials in Material Engineering Applications
- Page Range / eLocation ID:
- 285-316
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/https://doi.org/10.1007/978-3-030-62761-4_11
