ZnO-Co3O4 heterostructure electrospun nanofibers modified with poly(sodium 4-styrenesulfonate): Evaluation of humidity sensing properties

Author(s)

Andre, Rafaela S. ^[1] ; Pereira, Jessica C. ^{[1, 2]} ; Mercante, Luiza A. ^{[1, 3]} ; Locilento, Danilo ^{[4, 1]} ; Mattoso, Luiz H. C. ^{[1, 3]} ; Correa, Daniel S. ^{[4, 1]}

Affiliation

^[1] Embrapa Instrumentacao, Nanotechnol Natl Lab Agr LNNA, BR-13560970 Sao Carlos, SP - Brazil

^[2] Univ Sao Paulo, Sao Carlos Sch Engn EESC, BR-13566590 Sao Carlos, SP - Brazil

^[3] Fed Univ Sao Carlos UFSCar, Ctr Exact Sci & Technol, Dept Mat Engn, PPG CEM, BR-13565905 Sao Carlos, SP - Brazil

^[4] Fed Univ Sao Carlos UFSCar, Ctr Exact Sci & Technol, Dept Chem, PPGQ, BR-13565905 Sao Carlos, SP - Brazil

• Document type: Journal article
• Source: Journal of Alloys and Compounds; v. 767, p. 1022-1029, OCT 30 2018.
• Web of Science Citations: 6

Abstract

Nanostructured metal oxide semiconductors (MOS) based chemoresistive sensors play an important role in designing handheld, portable and cost-effective sensing systems for the detection of various target analytes. Herein, one-dimensional ZnO-Co3O4 heterostructure nanofibers (NFZCo) were successfully fabricated via electrospinning technique followed by a high-temperature treatment. The heterostructured nanofibers were fully characterized by scanning and transmission electron microscopy, X-ray diffraction, energy dispersive X-ray spectroscopy and X-ray photo-electron spectroscopy. Using poly (sodium 4-styrenesulfonate) (PSS), a strong anionic polyelectrolyte, to modify the NFZCo surface, a hybrid material (NFZCo-PSS) was prepared, which worked as a humidity sensor through a cost-effective approach. The humidity sensing properties of the hybrid nanomaterial were investigated by exposing it to a wide relative humidity range of 25-75%. The NFZCo-PSS modified electrode exhibited a fast and large response in terms of electrical resistance as the humidity was varied at room temperature. Moreover, the response time for the humidification process was determined as less than 5 s. In general, the sensing performance of the hybrid platform was greatly superior than that of pure NFZCo. Moreover, the humidity sensing mechanismwas ascribed to the synergistic effect of the nanofibers morphology and PSS toward water molecules. This work highlights that the hybrid NFZCo-PSS nanofibers can be used as active sensing nanostructures for humidity sensors application. (C) 2018 Elsevier B.V. All rights reserved. (AU)

• FAPESP's process: 16/23793-4 - Development of nanostructured sensor aiming the detection of volatile compounds for food quality indicators
• Grantee: Rafaela da Silveira Andre
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 17/12174-4 - Development of hybrid polymer nanofibers for agricultural applications
• Grantee: Daniel Souza Corrêa
• Support Opportunities: Regular Research Grants