Enhancement of Molten Nitrate Thermal Properties by Reduced Graphene Oxide and Graphene Quantum Dots

Esraa Hamdy; Laila Saad; Fuad Abulfotuh; Moataz Soliman; Shaker Ebrahim

doi:10.1021/acsomega.0c01291

Enhancement of Molten Nitrate Thermal Properties by Reduced Graphene Oxide and Graphene Quantum Dots

ACS Omega. 2020 Aug 20;5(34):21345-21354. doi: 10.1021/acsomega.0c01291. eCollection 2020 Sep 1.

Authors

Esraa Hamdy¹, Laila Saad², Fuad Abulfotuh¹, Moataz Soliman¹, Shaker Ebrahim¹

Affiliations

¹ Materials Science Department, Institute of Graduate Studies and Research, Alexandria University, Alexandria, P.O:832, 21526, Egypt.
² Renewable Energy Science and Engineering Department, Faculty of Postgraduate Studies for Advanced Sciences, Bani-Suef University, Beni Suef 62511, Egypt.

Abstract

Eutectic molten salts are the most studied medium-high temperature thermal energy storage material due to their potential use in concentrated solar power plants. The aim of this work is to investigate the effect of using reduced graphene oxide (RGO) and graphene quantum dots (GQDs) on the thermal properties of eutectic molten salts. A binary nitrate eutectic mixture of NaNO₃ and KNO₃ was selected as a base material (BM) for nitrate/carbon-derivative composites. RGO and GQDs were individually mixed with the BM with different fractions ranged from 0.1 to 1.5 wt %. The results showed that RGO enhanced the thermal conductivity, heat of fusion, and total thermal energy storage capacity by 52.10%, 44.48%, and 10.44%, respectively. GQDs slightly improved the specific heat capacity for both solid and liquid phases by 2.53% and 3.13%, respectively. In addition, GQDs promoted the heat of fusion by 31.72% and raised the total TES capacity by 12.26%.