Alagdal, I.A. and West, A.R. (2015) Oxygen non-stoichiometry, conductivity and gas sensor response of SnO2 pellets. Journal of Materials Chemistry A, 3 (46). 23213 -23219. ISSN 2050-7488
Abstract
SnO2 pellets lose a very small amount of oxygen at high temperatures to give, for instance, the stoichiometry SnO1.9989(1) at 1200°C in air. The oxygen deficiency, δ can be preserved at ambient temperature in quenched samples. The level of conductivity, which is n-type, depends on oxygen content, 2-δ and varies by several orders of magnitude; activation energies cover the range 1.1 eV for slow-cooled, fully oxidised samples to 0.52 eV for samples quenched from 1200°C. Quenched samples can be readily and reversibly reoxidised and reduced at temperatures as low as 700°C; at lower temperatures, down to ∼350°C, oxidation and reduction is mainly confined to sample surfaces on short timescales but, nevertheless, is sufficient for the conductivity to change by 1 to 2 orders of magnitude. Quenched, oxygen-deficient samples are also moisture-sensitive whereas fully oxidised samples are not. SnO2 shows similar sensitivity to both CO2 and N2, which is attributed to loss of O2 from the sample surface.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © Royal Society of Chemistry 2015. This is an author produced version of a paper subsequently published in Journal of Materials Chemistry A. Uploaded in accordance with the publisher's self-archiving policy. |
Dates: |
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Institution: | The University of Sheffield |
Academic Units: | The University of Sheffield > Faculty of Engineering (Sheffield) > Department of Materials Science and Engineering (Sheffield) |
Depositing User: | Symplectic Sheffield |
Date Deposited: | 08 Dec 2015 15:06 |
Last Modified: | 06 Nov 2017 06:55 |
Published Version: | http://dx.doi.org/10.1039/c5ta05818j |
Status: | Published |
Publisher: | Royal Society of Chemistry |
Refereed: | Yes |
Identification Number: | 10.1039/c5ta05818j |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:92550 |