Advanced search
Start date
Betweenand


Synthesis, characterization, and mechanistic study involved in the self-doping of TiO2 nanotubes simultaneously to the impedimetric detection of methylene blue

Full text
Author(s):
Soto, Pablo C. ; Martins, Joao V. ; Sarto, Gabrielle ; Slonski, Maiara M. ; Anizelli, Helder S. ; Ferreira, Elivelton A. ; Cervantes, Thiago N. M. ; Almeida, Lucio C.
Total Authors: 8
Document type: Journal article
Source: Journal of Solid State Electrochemistry; v. N/A, p. 14-pg., 2024-08-10.
Abstract

This paper reports that the self-doped TiO2 nanotubes (SD-TNT) electrode obtained by cathodic polarization promotes a significant decrease in the band gap value and an increase in electrode conductivity, due to the formation of Ti3+ sites and oxygen vacancies. A mechanism for the electrochemical self-doping of TNT electrode and its potential applicability as an impedimetric sensing platform for the target molecule methylene blue (MB) dye was proposed. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) studies made it possible to determine that the charge transfer process in the self-doping process is associated with the stability of H+ species. A 2(2) full factorial design (FFD) combined with response surface methodology (RSM) was employed to find the optimal operational conditions of the impedimetric sensor, which were equal to -1.4 V at pH 7.0. In this optimized condition, a linear relationship (R-2 = 0.999) for the MB concentration range of 0.10 to 1.75 mg L-1 as a function of the charge transfer resistance (R-ct) was found. Finally, it was possible to correlate the self-doping process of TNT with the impedimetric behavior, indicating that this system can be used for other cationic compounds of interest. (AU)

FAPESP's process: 14/50945-4 - INCT 2014: National Institute for Alternative Technologies of Detection, Toxicological Evaluation and Removal of Micropollutants and Radioactivies
Grantee:Maria Valnice Boldrin
Support Opportunities: Research Projects - Thematic Grants