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The form‐stabilized phase change materials (PCMs) comprised of lauric acid (LA), high‐density polyethylene (HDPE) and graphene nanoplates‐carbon nanofibers (GNP‐CNF) hybrid fillers were synthesized by melt blending method in this work, and the effects of GNP‐CNF mass ratio on thermal properties were investigated. The results from FT‐IR and XRD reveal that LA, HDPE, GNP and CNF were integrated with each other in a physical manner. The LA/HDPE/GNP‐CNF composites possess melting points very close to that of pure LA, with melting latent heats of 113.83–119.84 J/g. Thermal conductivity results indicate that the effect of GNP is better than that of CNF at the same content. The synergistic effect of hybrid carbon fillers can achieve higher thermal conductivity value compared to a single GNP or CNF. The synergistic thermal conductivity improvement mechanism is also analyzed. The sample SN2 (GNP: CNF is 1.7:0.3) exhibits the best thermal conductivity of 0.759 W/(m·K), with 2.73 times that of SN0. It also presents satisfactory thermal stability and reliability, allowing it to have promising applications in thermal energy storage. [ABSTRACT FROM AUTHOR]

This article reviews the state of the art of the formulation and fabrication of sensible, latent, and thermochemical thermal energy storage (TES) materials with special focus on the role of particle technology in enhancing the performance of these materials. Molten salt‐based sensible TES materials have been intensively studied, particularly the use of doped nanoparticles for enhancing specific heat capacity and thermal conductivity. For latent TES, the inclusion of property enhancers is among the most effective approaches to address the low thermal conductivity and supercooling issues of phase change materials (PCMs), whereas the encapsulation of PCMs and structurally stabilized composite PCMs are the favorable methods to address leakage and chemical incompatibility challenges. Thermochemical TES materials are often incorporated with an inert or an active host matrix for structural stabilization. [ABSTRACT FROM AUTHOR]

New sustainable carbon materials were synthesized from a low‐price and eco‐friendly carrot via hydrothermal reaction and carbonization approach. Afterwards, palmitic acid (PA) was impregnated into the carrot‐derived carbon material (CCM) to prepare PA@CCM composites through vacuum impregnation method. The thermal properties and shape stability of PA@CCM composites were evaluated by differential scanning calorimetry (DSC), thermal conductivity and thermal cycling tests. Owing to the special hybrid microstructure of the CCMs, the loading ratio of PA in PA@CCM composites could reach up to 85.3 % with the latent heat of 166.4 J g−1. More importantly, the PA@CCM composites show negligible leakage above the melting point of PA, exhibiting excellent shape stability. Compared with pristine PA, the thermal conductivity of PA@CCM composites could greatly enhanced by 145.5 %. Thus, PA@CCM composites can be considered as a promising candidate for thermal energy storage applications. [ABSTRACT FROM AUTHOR]

Thermal energy storage technologies based on phase‐change materials (PCMs) have received tremendous attention in recent years. These materials are capable of reversibly storing large amounts of thermal energy during the isothermal phase transition and offer enormous potential in the development of state‐of‐the‐art renewable energy infrastructure. Thermal conductivity plays a vital role in regulating the thermal charging and discharging rate of PCMs and improving the heat‐utilization efficiency. The strategies for tuning the thermal conductivity of PCMs and their potential energy applications, such as thermal energy harvesting and storage, thermal management of batteries, thermal diodes, and other forms of energy utilization, are summarized systematically. Furthermore, a research perspective is given to highlight emerging research directions of engineering advanced functional PCMs for energy applications. [ABSTRACT FROM AUTHOR]