☆ 4.7 Article

Hierarchically mesoporous SnO2 nanosheets: Hydrothermal synthesis and highly ethanol-sensitive properties operated at low temperature

SENSORS AND ACTUATORS B-CHEMICAL (2013)

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Journal

SENSORS AND ACTUATORS B-CHEMICAL
Volume 185, Issue -, Pages 594-601

Publisher

ELSEVIER SCIENCE SA
DOI: 10.1016/j.snb.2013.05.068

Keywords

SnO2 nanosheet; Mesopore; Ethanol sensor; High response; Low operating temperature

Categories

Chemistry, Analytical Electrochemistry Instruments & Instrumentation

Funding

  1. Starting Research Fund for Doctors in Tianjin University of Technology, PR China [115-401005005]

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In this contribution, hierarchical tin dioxide (SnO2) nanosheets were successfully synthesized via a simple, cost-effective and environment-friendly hydrothermal method at a relatively low temperature (90 degrees C) after calcination in air. The post-heat treatment not only improved the crystallinity, but also increased the visible emission (refer to intrinsic crystal defects) of the hydrothermal products, which were proved by X-ray diffraction and room temperature photoluminescence, respectively. Electronmicroscopy analysis and nitrogen adsorption-desorption results confirmed the mesoporous feature of these nanosheets. Gas sensors based on these SnO2 nanosheets exhibited high response, fast response-recovery and good selectivity to 1-1000 ppm ethanol vapor at a relatively low operating temperature (165 degrees C). The excellent ethanol-sensing property, especially high response value can be mainly attributed to the mesoporous texture, characteristically small grain size, abundant surface defects, and the plane-contact feature between the neighboring SnO2 nanosheets. (c) 2013 Elsevier B.V. All rights reserved.

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