Preparation and characterization of nano‐enhanced myristic acid using metal oxide nanoparticles for thermal energy storage

Abstract

Summary Fatty acids have been broadly used as phase change materials (PCMs) for thermal energy storage. However, low thermal conductivity limits their performances. This paper investigates the influence of metal oxide nanoparticle addition on myristic acid (MA) as nano‐enhanced PCM (NEPCM). Stability, chemical, and thermal properties were considered. Four types of nanoaprticles, TiO2, CuO, Al2O3, and ZnO, were dispersed in MA at 0.1, 0.5, 1, and 2 wt%. Stability and dispersion were checked by sediment photograph capturing and scanning electron microscopy/energy‐dispersive spectroscopy. The Fourier‐transformed infrared (FTIR) and X‐ray diffraction analysis confirmed no chemical interaction between the nanoparticles and MA. The results revealed a ratio of thermal conductivity of 1.50, 1.49, 1.45, and 1.37, respectively, for 2 wt% of ZnO, Al2O3, CuO, and TiO2. The T‐history method confirmed this enhancement. The latent heat thermal energy storage (LHTES) properties of the nano‐enhanced MA were evaluated using differential scanning calorimetry. The latent heat capacities of nano‐enhanced MA samples have dropped between 9.64 and 5.01 % compared with pure MA, and phase change temperature range was not affected significantly. The NEPCM was subjected to 500 thermal cycling, it showed a good thermal reliability as LHTES properties remained unchanged, while FTIR analysis showed similar characteristics compared with uncycled samples, indicating a good chemical stability. Based on the results regarding with the LHTES properties, cycling thermal reliability, and higher thermal conductivity improvement, it can be achieved that the MA/Al2O3 (2.0 wt%) and MA/ZnO (2.0 wt%) composites could be better PCMs for solar TES applications.

Applying artificial neural networks to predict the enhanced thermal conductivity of a phase change material with dispersed oxide nanoparticles

“…13 Many researchers have extensively investigated enhanced TC of PCMs containing various nanostructured materials such as metallic nanoparticles, 14,15 carbon-based nanomaterials, [16][17][18] and oxide nanoparticles. [19][20][21] Table 1 demonstrates the list of some recent studies [22][23][24][25][26][27][28][29][30][31][32][33] on enhanced TC of PCMs with dispersed oxide nanoparticles and reports the TC enhancement for all nanoparticle loadings and temperatures. As shown in Table 1, some discrepancies can be found between various references due to materials, preparation methods, and measurement techniques.…”

Interactions between hybrid nanosized particles and convection melting inside an enclosure with partially active walls: 2D lattice Boltzmann‐based numerical investigation

“…The butyl stearate/multiwalled carbon nanotube (MWCNT) composite with a weight fraction of 0.02 was recommended for the TES systems. Ouikhalfan et al 20 experimentally explored the effects of metal oxide nanoparticles (TiO 2 , CuO, alumina, and ZnO) with the volume fractions lower than 0.02 on the melting/freezing of the myristic acid (MA). The thermal conductivity of the base PCM was escalated by 1.50, 1.49, 1.45, and 1.37 times when ZnO, Al 2 O 3 , CuO, and TiO 2 nanoparticles with the volume fraction of 0.02 were added, respectively.…”

Development and characterization of form‐stable porous TiO 2 /tetradecanoic acid based composite PCM with long‐term stability as solar thermal energy storage material

“…Hussain SI et al 19 prepared nanoencapsulated oleic acid‐PEG with LHS values for melting/solidification of 58.79/55.49 J/g and an encapsulation ratio of 52.12%. Ouikhalfan et al 35 added to CuO, Al 2 O 3 , TiO 2 , and ZnO nanoparticles to myristic acid as base PCM and reported that the fabricated composites showed good chemical and thermal stability after 500 melt‐freeze cycles. In a very recent experimental investigation, the dispersion stability of the TiO 2 ‐Ag nanoparticles in molten paraffin wax as PCM was studied using a surfactant agent, and they reported that TiO 2 ‐Ag nanocomposite had uniform dispersion and improved thermal properties 36 .…”