Enhancing the specific heat capacity of molten salts by nanoparticle dispersion has emerged as a means to reduce the capital costs of thermal storage for concentrating solar thermal power plants, enabling cheaper solar electricity. Although several studies have shown near 30% enhancement in the specific heat of nanosalts other studies have reported a decrease of similar magnitude. In order to explain discrepancies reported in the literature, this study investigates the influence of various nanoparticle morphologies and preparation methods on the specific heat of nanosalts, which has not been systematically explored. To date, the extent of initial dispersion and the dispersion stability have only been reported on an ad-hoc basis in the literature. In the present study surface chemistry and sonication energy are controlled independently during preparation. By controlling both of these factors, the change of specific heat in nanosalts, results of this study present achieving up to 18% enhancement in specific heat of nanosalts by preparing an optimal nanosalt with distinctive nanoparticles. (C) 2015 Elsevier Ltd. All rights reserved.