Thermodynamic behavior and polymorphism of 1-butyl-3-methylimidazolium hexafluorophosphate composites with multiwalled carbon nanotubes

Published

November 10, 2018

Author(s)

Tatsiana Liavitskaya, Eugene Paulechka, Andrey V. Blokhin, Marina Shevelyova

Abstract

Based on the measured densities of ionic nanofluids (INF) with different ionic liquids (ILs), it was concluded that evacuation is a necessary step to maximize the IL penetration to multiwalled carbon nanotubes (MWCNT). An improved procedure for reproducible preparation of INF was proposed. Thermal behavior of the 1-butyl-3-methylimidazolium hexafluorophosphate composites with MWCNT was studied by adiabatic calorimetry over the temperature range of (78 to 370) K. The composites contained from 0.11 to 0.92 mass fraction of the nanophase. For the fluid samples, the specific heat capacity was found be an additive quantity of specific heat capacities of the components for the crystal and liquid phases. The temperatures of phase transitions did not change relative to the bulk values. For the powder-like sample with a high IL content, the sigmoidal heat capacity curve was observed. Thus, the internal diameter of the studied MWCNT was small enough to switch from the isothermal melting process to the gradual transition from the crystal-like structures to the liquid-like ones. It was demonstrated that, in the liquid-like region, the heat capacity of the nanophase may be higher than that of pure MWCNT.

Citation

Journal of Chemical Thermodynamics

Volume

131

Pub Type

Journals

Download Paper

https://doi.org/10.1016/j.jct.2018.11.006

Local Download

Citation

Liavitskaya, T. , Paulechka, E. , Blokhin, A. and Shevelyova, M. (2018), Thermodynamic behavior and polymorphism of 1-butyl-3-methylimidazolium hexafluorophosphate composites with multiwalled carbon nanotubes, Journal of Chemical Thermodynamics, [online], https://doi.org/10.1016/j.jct.2018.11.006, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=926717 (Accessed December 12, 2024)