Scientific Results

Optical and dielectric properties of ethylene glycol-based nanofluids containing nanodiamonds with various purities

Year: 2019

Authors: Di Rosa D., Wanic M., Fal J., Żyła G., Mercatelli L., Sani E.

Autors Affiliation: National Institute of Optics (CNR-INO), Largo E. Fermi 6, 50125 Firenze, Italy; Department of Physics and Medical Engineering, Rzeszow University of Technology, al. PowstańcówWarszawy 12, 35-959 Rzeszów, Poland

Abstract: Thework reports on the characterization of optical and dielectric properties of nanofluids consisting in pure nanodiamonds suspended in ethylene glycol. The study is carried out at four concentrations within the range from 0.01 to 0.1 wt%, and for two different types of nanodiamond powders, differing each other in the purity of the diamond phase (87% or 97%). Optical extinction, even at the investigated extremely low concentrations, results significantly increased in the colloids with respect to the pure base fluid, while the refractive index at 589.3 nm remains practically unchanged. Dielectric properties of nanofluids are related with the content of nanodiamonds particles. While the complex permittivity of tested samples is dependent on a small extent, the electrical conductivity is strongly affected by the increase of nanodiamond concentration. © 2019 Elsevier B.V.

Journal/Review: POWDER TECHNOLOGY

Volume: 356      Pages from: 508  to: 516

KeyWords: Nanodiamonds
Nanofluids
Solar collectors
Optical properties
Dielectric properties
Solar absorption
DOI: https://doi.org/10.1016/j.powtec.2019.08.036

English