Journal
JOURNAL OF ALLOYS AND COMPOUNDS
Volume 681, Issue -, Pages 43-49Publisher
ELSEVIER SCIENCE SA
DOI: 10.1016/j.jallcom.2016.04.220
Keywords
Vacuum annealing; Oxygen vacancies; SnO2; Room temperature gas sensing
Categories
Funding
- National Natural Science Foundation of China [20901029]
Ask authors/readers for more resources
SnO2 oxide nanocrystals were synthesized by annealing the precursor powders at 550 degrees C in vacuum and air environment, respectively. The nanocrystals were characterized by using techniques including X-ray diffraction, transmission electron microscopy, UV-Vis diffuse reflectance spectra, and X-ray photoelectron spectroscopy. It was found that the SnO2 nanocrystals obtained in vacuum contained more oxygen vacancies than the SnO2 nanocrystals prepared in air. When used as gas sensors, the SnO2 nanocrystals prepared in vacuum showed much enhanced room temperature sensing performance to NO2 gas relative to the SnO2 nanocrystals prepared in air. This result confirms the important role of oxygen vacancies in improving gas response of the oxide nanocrystals. The oxygen vacancies make the grain surface possess special chemistry state thereby improving the NO2 adsorption at low operating temperatures and enhancing the charge transfer from the surface to the adsorbate. It suggests that the vacuum annealing is a valid method to generate oxygen vacancies in SnO2 nanocrystals. Such synthetic method with the merits of simplicity and no using any surfactants or additives may pave the way to acquire other oxides with oxygen vacancies thereby being used as advanced materials. (C) 2016 Elsevier B.V. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available