Zinc Nanoparticles Electrodeposited on TiO₂Nanotube Arrays Using Deep Eutectic Solvents for Implantable Electrochemical Sensors

Abstract

This work reports on the electrodeposition of zinc on nanoporous metal oxide titania nanotube arrays (TiO2 NTAs) using a zinc-containing deep eutectic solvent (Zn2+–DES). The effects of substrate morphology and crystallinity, deposition temperature, zinc concentration, and deposition time on the morphology and electrochemical properties of the Zn/TiO2 NTAs were investigated. Two-dimensional zinc nanohexagons (NHexs) with a mean diameter of ∼300 nm and a thickness of 10–20 nm were decorated onto the TiO2 NTAs (with a pore diameter of ∼80 nm and a tube length of ∼5 μm) via electrodeposition at −1.6 V using Zn2+–DES. Cyclic voltammetry tests on the Zn2+–DES electrolyte revealed an electrochemical window of ∼3.5 V, and the diffusion coefficient of Zn2+ was found to be 4.29 × 10–10 cm2 s–1 at room temperature and 7.10 × 10–10 cm2 s–1 at 40 °C. Zinc nucleation on TiO2 NTA substrates followed an instantaneous model. Using a higher electrodeposition temperature increased the nucleation and growth rate of zinc NHexs, while annealing TiO2 NTAs was found to improve their uniformity and morphology. During the initial stage of deposition, hexagonal close-packed zinc NHexs were found to preferentially grow on tetragonal anatase TiO2 NTAs. The electrodeposition of zinc resulted in lowering the impedance and improving the overall electrochemical properties of TiO2 NTAs. The Zn/TiO2 NTAs developed in this study offer a promising electrocatalyst material system for implantable electrochemical sensors.

Deep eutectic solvents induced changes in the phase transition behavior of smart polymers: a sustainable future approach

“…Specifically, in the field of nanoscience and nanotechnology, DESs have been regarded as designer solvents. 15,16,27,28 DESs can be used to synthesize well-defined nanomaterials such as shape and size-controlled nanoparticles, 29–31 metal–organic frameworks, 32 electrodeposited films, 33,34 colloidal assemblies, 35 RNA/DNA architectures, 36,37 and hierarchically porous carbons. 27 DESs have been utilized as a suitable medium for the synthesis of functional and nanoscale materials.…”

“…Cojocaru et al 33 utilized DESs to fabricate electrodeposited CoSm films. Wang et al 34 reported on the electrodeposition of zinc nanoparticles on titanium oxide nanotube arrays using DESs. Siegel et al 35 summarized the progress and prospects in synthesizing the colloidal nanoparticles and colloidal assemblies using DESs.…”

Ultrasonically Assembled 0-D Zirconium Oxide on TiO2 Nanorod for a Sensitive Determination of Antibiotic Drug in Biological Samples

“…This nanocomposite already shows a good result in medical assessment process by reason of its higher surface volume proportion, less toxic, synthetic solidness, high isoelectric point, biocompatibility and proposed electron transfer is maximum. [24][25][26][27] An electrochemical sensor based on TiO 2 /ZrO 2 has been reported for the first time in this field.…”