Electrical Conductivity and Dielectric Properties of Ethylene Glycol-Based Nanofluids Containing Silicon Oxide–Lignin Hybrid Particles

• Main Authors: Jacek Fal, Michał Wanic, Grzegorz Budzik, Mariusz Oleksy, Gaweł Żyła
• Format: Article
• Language: English
• Published: MDPI AG 2019-07-01
• Series: Nanomaterials
• Subjects: silica; silicon oxide; lignin; nanofluids; nanoparticles; electrical properties
• Online Access: https://www.mdpi.com/2079-4991/9/7/1008

This paper presents results of experimental investigation into dielectric properties of silicon oxide lignin (SiO₂-L) particles dispersed with various mass fractions in ethylene glycol (EG). Measurements were conducted at a controlled temperature, which was changed from 298.15 to 333.15 K with an accuracy of 0.5 and 0.2 K for dielectric properties and direct current (DC) electrical conductivity, respectively. Dielectric properties were measured with a broadband dielectric spectroscopy device in a frequency range from 0.1 to 1 MHz, while DC conductivity was investigated using a conductivity meter MultiLine 3410 working with LR925/01 conductivity probe. Obtained results indicate that addition of even a small amount of SiO₂-L nanoparticles to ethylene glycol cause a significant increase in permittivity and alternating current (AC) conductivity as well as DC conductivity, while relaxation time decrease. Additionally, both measurement methods of electrical conductivity are in good agreement.