Title
Remarkably Enhanced Room-Temperature Hydrogen Sensing of SnO2 Nanoflowers via Vacuum Annealing Treatment.
Abstract
In this work, SnO2 nanoflowers synthesized by a hydrothermal method were employed as hydrogen sensing materials. The as-synthesized SnO2 nanoflowers consisted of cuboid-like SnO2 nanorods with tetragonal structures. A great increase in the relative content of surface-adsorbed oxygen was observed after the vacuum annealing treatment, and this increase could have been due to the increase in surface oxygen vacancies serving as preferential adsorption sites for oxygen species. Annealing treatment resulted in an 8% increase in the specific surface area of the samples. Moreover, the conductivity of the sensors decreased after the annealing treatment, which should be attributed to the increase in electron scattering around the defects and the compensated donor behavior of the oxygen vacancies due to the surface oxygen adsorption. The hydrogen sensors of the annealed samples, compared to those of the unannealed samples, exhibited a much higher sensitivity and faster response rate. The sensor response factor and response rate increased from 27.1% to 80.2% and 0.34%/s to 1.15%/s, respectively. This remarkable enhancement in sensing performance induced by the annealing treatment could be attributed to the larger specific surface areas and higher amount of surface-adsorbed oxygen, which provides a greater reaction space for hydrogen. Moreover, the sensors with annealed SnO2 nanoflowers also exhibited high selectivity towards hydrogen against CH4, CO, and ethanol.
Year
DOI
Venue
2018
10.3390/s18040949
SENSORS
Keywords
Field
DocType
hydrogen sensing,SnO2,annealing,nanoflowers,hydrothermal
Conductivity,Hydrogen,Analytical chemistry,Tetragonal crystal system,Oxygen,Nanorod,Annealing (metallurgy),Adsorption,Engineering,Specific surface area
Journal
Volume
Issue
Citations 
18
4.0
1
PageRank 
References 
Authors
0.43
1
10
Name
Order
Citations
PageRank
Gao Liu110.43
Zhao Wang210.43
Zihui Chen310.43
Shulin Yang410.43
Xingxing Fu510.43
Rui Huang66123.21
Xiaokang Li710.43
Juan Xiong821.48
Yongming Hu910.77
Hao Gu1012.12