Influence of geometry and annealing temperature in argon atmosphere of TiO₂ nanotubes on their electrochemical properties.

Nycz, Marta; Paradowska, Ewa; Arkusz, Katarzyna; Pijanowska, Dorota Genowefa

Purpose: This paper presents electrochemical properties of the as-formed and thermally treated titanium dioxide (TiO2) nanotubes with diameter in range 20-100 nm and height in range of 100-1000 nm. In addition, the effects of annealing temperature (450-550 °C) on the electrochemical characteristics of these structures, as well as the influence of diameter and height of TiO2 nanotubes on these properties were examined. The results were referred to a compact TiO2 layer (100 nm - thick). Methods: The electrochemical test included open circuit potential, impedance spectroscopy and cyclic voltammetry measurements. The scanning electron microscope with energy dispersive spectroscopy analyser, x-ray photoelectron spectroscopy, and x-ray diffraction analysers were used for surface morphology characterisation as well as elemental, phase and chemical composition of TiO2 layers. Results: It was found that nanotubes with the diameter of 50 and 75 nm (height of 1000 nm) annealed at 550 °C exhibit the lowest impedance and phase angle values. However, the voltammetric detection of potassium ferricyanide indicated that the closest to 1 Ipc/Ipa ratio showed nanotubes with a diameter of 50 and 75 nm annealed at 450 °C. Conclusions: On the basis of performed analysis it can be stated that the TiO2 layer with nanotubes diameter of 50 nm and height of 1000 nm, annealed in 450 °C may be indicated as having the most favourable sensing and biosensing properties.

NANOTUBES; ANNEALING of metals; ENERGY dispersive X-ray spectroscopy; X-ray photoelectron spectroscopy; SCANNING electron microscopes; ARGON; CYCLIC voltammetry; IMPEDANCE spectroscopy

Acta of Bioengineering & Biomechanics, 2020, Vol 22, Issue 1, p1

1509-409X

Academic Journal

10.37190/abb-01479-2019-03