Publication
Title
Sensitivity of nanocrystalline tungsten oxide to CO and ammonia gas determined by surface catalysts
Author
Abstract
Nanocrystalline tungsten oxide with variable particle size and surface area was synthesized by aqueous deposition and heat treatment for use in resistive gas sensors. Surface modification with 1 wt.% Pd and Ru was performed by impregnation to improve the sensitivity to CO and ammonia. Acid and oxidation surface sites were evaluated by temperature-programmed techniques using probe molecules. The surface acidity dropped with increasing particle size, and was weakly affected by additives. Lower crystallinity of WO3 and the presence of Ru species favoured temperature-programmed reduction of the materials. Modifying WO3 increased its sensitivity, to CO at ambient condition for modification by Pd and to NH3 at elevated temperature for Ru modification. An in situ infrared study of the gas - solid interaction showed that the catalytic additives change the interaction route of tungsten oxide with the target gases and make the reception of detected molecules independent of the semiconductor oxide matrix.
Language
English
Source (journal)
Sensors and actuators : B : chemical. - Lausanne
Publication
Lausanne : 2018
ISSN
0925-4005
DOI
10.1016/J.SNB.2018.09.004
Volume/pages
277 (2018) , p. 336-346
ISI
000453066700042
Full text (Publisher's DOI)
Full text (open access)
Full text (publisher's version - intranet only)
UAntwerpen
Faculty/Department
Research group
Publication type
Subject
Affiliation
Publications with a UAntwerp address
External links
Web of Science
Record
Identifier
Creation 18.01.2019
Last edited 09.10.2023
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