Titanium dioxide-graphene composite electrochemical sensor for detection of hexavalent chromium
Issued Date
2022-03-01
Resource Type
ISSN
16744799
eISSN
1869103X
Scopus ID
2-s2.0-85123789075
Journal Title
International Journal of Minerals, Metallurgy and Materials
Volume
29
Issue
3
Start Page
529
End Page
535
Rights Holder(s)
SCOPUS
Bibliographic Citation
International Journal of Minerals, Metallurgy and Materials Vol.29 No.3 (2022) , 529-535
Suggested Citation
Pienutsa N., Yannawibut K., Phattharaphongmanee J., Thonganantakul O., Srinives S. Titanium dioxide-graphene composite electrochemical sensor for detection of hexavalent chromium. International Journal of Minerals, Metallurgy and Materials Vol.29 No.3 (2022) , 529-535. 535. doi:10.1007/s12613-021-2338-7 Retrieved from: https://repository.li.mahidol.ac.th/handle/20.500.14594/84600
Title
Titanium dioxide-graphene composite electrochemical sensor for detection of hexavalent chromium
Author's Affiliation
Other Contributor(s)
Abstract
Hexavalent chromium (Cr(VI)) compound is useful to various industries but is toxic and carcinogenic. In this research work, we fabricate an amperometric sensor for the determination of Cr(VI), using a titanium dioxide (TiO2)-reduced graphene oxide (rGO) composite as the sensing element. The composite was synthesized following sol—gel chemistry, yielding TiO2 nanoparticles of ∼50 nm in size, immobilized on chemically exfoliated rGO sheets. The composite was employed in a 3-electrode electrochemical cell and operated in an amperometric mode, exhibiting good responses to the 50 to 500 ppb Cr(VI). Our best result from pH 3 Mcilvane’s buffer medium reveals the sensitivity of 9.12 × 10−4 ppb−1 and a detection limit of 6 ppb with no signal interference from 200 ppm Ca(II), 150 ppm Mg(II), and 50 ppb Pb(II). The excellent results of the TiO2-rGO sensor can be attributed to synergic effects between TiO2 and rGO, resulting from the presence of n-p heterojunctions and the formation of the TiO2 nanoparticles on rGO.