Publication: Effect of Adsorbed Water and Temperature on the Universal Power Law Behavior of Lepidocrocite-Type Alkali Titanate Ceramics
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Issued Date
2021
Resource Type
Language
eng
File Type
application/pdf
ISSN
19327447
Other identifier(s)
2-s2.0-85108892999
Rights Holder(s)
Scopus
Bibliographic Citation
Journal of Physical Chemistry C. Vol 125, No.23 (2021), p.12910-12920
Suggested Citation
Sriphan S., Pulphol P., Charoonsuk T., Maluangnont T., Vittayakorn N. Effect of Adsorbed Water and Temperature on the Universal Power Law Behavior of Lepidocrocite-Type Alkali Titanate Ceramics. Journal of Physical Chemistry C. Vol 125, No.23 (2021), p.12910-12920. doi:10.1021/acs.jpcc.1c02221 Retrieved from: https://hdl.handle.net/20.500.14740/7127
Abstract
The ubiquitous (re)adsorption of atmospheric water by functional ceramics leads to some applications such as humidity sensing; at the same time, this phenomenon complicates the understanding of the nature of original conducting species. We presented herein the effects of adsorbed water on the electrical properties and charge transport of K0.8Zn0.4Ti1.6O4, Cs0.7Zn0.35Ti1.65O4, and Cs0.6K0.1Zn0.35Ti1.65O4 lepidocrocite-type alkali titanate ceramics. A small amount of atmospheric water (0.02-0.33 mol/mol) is merely adsorbed on the external surface but not intercalated into the interlayer space. In temperature scan experiments, water sorption leads to the dielectric permittivity/loss hysteresis loops, where the values upon cooling are unusually larger than those upon heating. In frequency scan experiments, multiple frequency- and temperature-dependent anomalies are detected. The AC conductivity was fitted to the Jonscher universal power law response (σ′AC = σDC + Aωs) from 101 to 106 Hz and 400-25 °C. We observed an uncommon U-shaped A(T) but an inverted U-shaped s(T), regardless of the interlayer ion, charge per formula unit, or pellet density. These plots allow a qualitative description of (i) the apparent activation energy, (ii) the effective dimension of the conduction pathway, and (iii) the charge carrier concentration, all as a function of the temperature under the influence of atmospheric water. Our physical interpretation is potentially applicable to other systems, providing insights into the (unintentional) water-induced conductions and complementing rigorous but time-consuming investigations by controlled humidity experiments. © 2021 American Chemical Society.
Subject(s)
Activation energy
Atmospheric humidity
Carrier concentration
Cesium compounds
Humidity control
Humidity sensors
Permittivity
Potassium compounds
Titanium compounds
Zinc compounds
Apparent activation energy
Controlled humidities
Dielectric permittivities
Effective dimensions
Functional ceramics
Physical interpretation
Temperature dependent
Universal power law
Atmospheric temperature
Atmospheric humidity
Carrier concentration
Cesium compounds
Humidity control
Humidity sensors
Permittivity
Potassium compounds
Titanium compounds
Zinc compounds
Apparent activation energy
Controlled humidities
Dielectric permittivities
Effective dimensions
Functional ceramics
Physical interpretation
Temperature dependent
Universal power law
Atmospheric temperature