Gas sensing behavior of p-NiO/n-ZnO composite nanofibers depending on varying p-NiO content: Selectivity and humidity-independence for oxidizing and reducing gas molecules

In this work, we fabricated gas sensors based on p-type NiO/n-type ZnO composite nanofibers (NFs), which could selectively detect oxidizing and reducing gas molecules. The p-type NiO/n-type ZnO composite NFs with both hetero- and homojunctions were successfully synthesized, and their sensing perform...

Full description

Saved in:
Bibliographic Details
Published in:Sensors and actuators. B, Chemical Chemical, 2021-12, Vol.349, p.130813, Article 130813
Main Authors: Jin, Changhyun, Choi, Myung Sik, Lee, Kyu Hyoung, Choi, Sun-Woo
Format: Article
Language:English
Subjects:
Ammonia
Composite nanofibers
Composition
Gas sensors
Gases
Homojunctions
Humidity
Humidity independence
n-ZnO
Nanofibers
Nickel oxides
Nitrogen dioxide
Oxidation
p-NiO
Selectivity
Water chemistry
Zinc oxide
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:In this work, we fabricated gas sensors based on p-type NiO/n-type ZnO composite nanofibers (NFs), which could selectively detect oxidizing and reducing gas molecules. The p-type NiO/n-type ZnO composite NFs with both hetero- and homojunctions were successfully synthesized, and their sensing performances for oxidizing and reducing gases were systematically investigated with different composition ratios of p-type NiO and n-type ZnO. Interestingly, for oxidizing and reducing gases, the 0.5NiO-0.5ZnO NFs (nominal composition) exhibited an excellent gas response to oxidizing gases such as NO2 and SO2, whereas the 0.8NiO-0.2ZnO NFs (nominal composition) showed good selectivity for reducing gases such as C3H6O, C2H5OH, and NH3. In addition, we also examined the NO2 and CO sensing performance under a humid atmosphere to confirm the role of the NiO component, which possesses high affinity for water molecules, in p-type NiO/n-type ZnO composite NFs. We discussed the correlation between variations in composition and sensing performances with respect to gas sensing behavior, selectivity, and humidity effect for oxidizing and reducing gases. The results reveal that we successfully imparted selectivity for oxidizing and reducing gas molecules to the p-type NiO/n-type ZnO composite NFs by adjusting the composition ratio of NiO/ZnO. •High selectivity to oxidizing gases were realized using the composite nanofibers.•High selectivity to reducing gases were achieved using the composite nanofibers.•Humidity-independent nanofiber-based sensors were demonstrated.
ISSN:0925-4005
1873-3077
DOI:10.1016/j.snb.2021.130813