Processes associated with ionic current rectification at a 2D-titanate nanosheet deposit on a microhole poly(ethylene terephthalate) substrate
(2019) In Journal of Solid State Electrochemistry 23(4). p.1237-1248- Abstract
Films of titanate nanosheets (approx. 1.8-nm layer thickness and 200-nm size) having a lamellar structure can form electrolyte-filled semi-permeable channels containing tetrabutylammonium cations. By evaporation of a colloidal solution, persistent deposits are readily formed with approx. 10-μm thickness on a 6-μm-thick poly(ethylene-terephthalate) (PET) substrate with a 20-μm diameter microhole. When immersed in aqueous solution, the titanate nanosheets exhibit a p.z.c. of − 37 mV, consistent with the formation of a cation conducting (semi-permeable) deposit. With a sufficiently low ionic strength in the aqueous electrolyte, ionic current rectification is observed (cationic diode behaviour). Currents can be... (More)
Films of titanate nanosheets (approx. 1.8-nm layer thickness and 200-nm size) having a lamellar structure can form electrolyte-filled semi-permeable channels containing tetrabutylammonium cations. By evaporation of a colloidal solution, persistent deposits are readily formed with approx. 10-μm thickness on a 6-μm-thick poly(ethylene-terephthalate) (PET) substrate with a 20-μm diameter microhole. When immersed in aqueous solution, the titanate nanosheets exhibit a p.z.c. of − 37 mV, consistent with the formation of a cation conducting (semi-permeable) deposit. With a sufficiently low ionic strength in the aqueous electrolyte, ionic current rectification is observed (cationic diode behaviour). Currents can be dissected into (i) electrolyte cation transport, (ii) electrolyte anion transport and (iii) water heterolysis causing additional proton transport. For all types of electrolyte cations, a water heterolysis mechanism is observed. For Ca 2+ and Mg 2+ ions, water heterolysis causes ion current blocking, presumably due to localised hydroxide-induced precipitation processes. Aqueous NBu 4 + is shown to ‘invert’ the diode effect (from cationic to anionic diode). Potential for applications in desalination and/or ion sensing are discussed.
(Less)
- author
- publishing date
- 2019-04-12
- type
- Contribution to journal
- publication status
- published
- keywords
- Ion valve, Ionic logic, Iontronics, Nanostructure, Sensing, Voltammetry
- in
- Journal of Solid State Electrochemistry
- volume
- 23
- issue
- 4
- pages
- 12 pages
- publisher
- Springer
- external identifiers
-
- scopus:85062040723
- ISSN
- 1432-8488
- DOI
- 10.1007/s10008-019-04199-4
- language
- English
- LU publication?
- no
- additional info
- Publisher Copyright: © 2019, The Author(s).
- id
- 06ca1334-ac20-4a70-9696-cdef917d246c
- date added to LUP
- 2023-01-18 09:07:00
- date last changed
- 2023-02-03 11:27:48
@article{06ca1334-ac20-4a70-9696-cdef917d246c, abstract = {{<p> Films of titanate nanosheets (approx. 1.8-nm layer thickness and 200-nm size) having a lamellar structure can form electrolyte-filled semi-permeable channels containing tetrabutylammonium cations. By evaporation of a colloidal solution, persistent deposits are readily formed with approx. 10-μm thickness on a 6-μm-thick poly(ethylene-terephthalate) (PET) substrate with a 20-μm diameter microhole. When immersed in aqueous solution, the titanate nanosheets exhibit a p.z.c. of − 37 mV, consistent with the formation of a cation conducting (semi-permeable) deposit. With a sufficiently low ionic strength in the aqueous electrolyte, ionic current rectification is observed (cationic diode behaviour). Currents can be dissected into (i) electrolyte cation transport, (ii) electrolyte anion transport and (iii) water heterolysis causing additional proton transport. For all types of electrolyte cations, a water heterolysis mechanism is observed. For Ca <sup>2+</sup> and Mg <sup>2+</sup> ions, water heterolysis causes ion current blocking, presumably due to localised hydroxide-induced precipitation processes. Aqueous NBu <sub>4</sub> <sup>+</sup> is shown to ‘invert’ the diode effect (from cationic to anionic diode). Potential for applications in desalination and/or ion sensing are discussed.<br/></p>}}, author = {{Putra, Budi Riza and Harito, Christian and Bavykin, Dmitry V. and Walsh, Frank C. and Wahyuni, Wulan Tri and Boswell, Jacob A. and Squires, Adam M. and Schmitt, Julien M. F. and Da Silva, Marcelo Alves and Edler, Karen J. and Fletcher, Philip J. and Gesell, Anne E. and Marken, Frank}}, issn = {{1432-8488}}, keywords = {{Ion valve; Ionic logic; Iontronics; Nanostructure; Sensing; Voltammetry}}, language = {{eng}}, month = {{04}}, number = {{4}}, pages = {{1237--1248}}, publisher = {{Springer}}, series = {{Journal of Solid State Electrochemistry}}, title = {{Processes associated with ionic current rectification at a 2D-titanate nanosheet deposit on a microhole poly(ethylene terephthalate) substrate}}, url = {{http://dx.doi.org/10.1007/s10008-019-04199-4}}, doi = {{10.1007/s10008-019-04199-4}}, volume = {{23}}, year = {{2019}}, }