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Shape-stabilized phase change material (SSPCM) are widely used as energy storage materials due to its advantages of easy preparation and adjustable scale. But the thermal conductivity enhancement of SSPCM still need to be further studied to improve the energy storage efficiency. In this work, silicone rubber (SR)/paraffin@SiO 2 (Pn@SiO 2)/graphene nanoplates (GNPs) shape-stabilized phase change materials (SPG) with different GNPs content were prepared. Pn@SiO 2 and GNPs can be homogeneously dispersed in the SR matrix due to the enhanced interfacial compatibility between Pn@SiO 2 and SR. The leakage rate of SPG composites was as low as 0.25% due to the protection of SiO 2 shell, SR matrix and GNPs. The SPG composites had excellent thermal storage properties, with the enthalpy about 50 J·g−1. The thermal conductivity of SPG composites was improved with the content of GNPs, the thermal conductivity of SPG reach 0.989 W·m−1·K−1 at a GNPs content of 10 phr. The low hardness of SPG composites above the phase change temperature can provide a more cohesive surface when applied to heat dissipation. The heat dissipation of the SPG composites in electric devices was simulated and demonstrated that the addition of GNPs made the heat dissipation rate of the SPG composites increased significantly. Therefore, the SPG composites can be applied in thermal energy storage and heat dissipation of electronic devices. [Display omitted] • The thermal conductivity enhancement of SSPCM was further discussed. • The interfacial compatibility of components in the SSPCM was enhanced by the rational strategy. • The leakage-prevention performance of SSPCM was improved with the multiple protection. • The thermal conductivity of SSPCM reach 0.989 W·m−1·K−1 due to the well-dispersed GNPs and Pn@SiO 2 in SR. • Numerical simulation was used to predict the thermal performance of SPG composites. [ABSTRACT FROM AUTHOR]

Inorganic hydrated salts possess high latent heat of phase transition and are promising phase change materials (PCMs). However, the issues of supercooling, low thermal conductivity, susceptibility to leakage, and phase separation significantly impediment the practical applications of inorganic hydrated salts. In this study, it is proposed to decrease the inorganic hydrated salt supercooling degree by increasing the surface roughness of the porous material and to load the nucleating agent silver (Ag) onto polydopamine (PDA) modified melamine foam (MF) by electroless plating to obtain 3D porous Ag foams, which are then utilized as support materials. The results demonstrated that the 3D porous Ag foam compounded with barium hydroxide octahydrate (BHO) can ameliorate the shortcomings of leakage and reduce the supercooling degree in the cooling process. The composite not only exhibits high enthalpy of over 248.5 J/g and high thermal conductivity of 1.82 W·m−1·K−1 but also has a low supercooling degree of 0.21 ℃. Furthermore, the composites exhibited superior shape stability and thermal cycling stability. This study provides an effective method for reducing the supercooling degree of inorganic hydration salts. [Display omitted] [ABSTRACT FROM AUTHOR]

Hydrated salt phase change materials (PCMs) have the advantages of high energy storage density and low cost, and have great application prospects in the field of phase change energy storage. However, the problems of supercooling, phase separation and leakage of hydrated salt PCMs limit their further applications. In this work, we designed and fabricated Cu-coated melamine foam (MF)/barium hydroxide octahydrate (BHO) shape-stabilized phase change materials (SSPCMs) with low supercooling. MF was used as supporting material and Cu as a nucleating agent and thermal conductivity enhancer by loading it onto MF via electroless plating. BHO was then encapsulated into the MF@Cu skeleton through vacuum impregnation to obtain BHO@MF@Cu SSPCMs. The results demonstrated that BHO@MF@Cu SSPCMs not only present very low supercooling degree of 0.12 °C and high thermal energy capacity of 247 J/g, but maintained a latent heat of phase transition of 229.3 J/g with little change in enthalpy after 100 thermal cycles. Moreover, compared to BHO, SSPCMs exhibited high thermal conductivity of 1.687 W m−1 K−1, excellent shape stability, and thermal cycling stability. In summary, BHO@MF@Cu SSPCMs with low supercooling degree were prepared by electroless plating and vacuum impregnation in this study, which provides a new strategy to reduce the supercooling degree of hydrated salt PCMs. [Display omitted] [ABSTRACT FROM AUTHOR]

A series of reversibly thermochromic phase-change microcapsules (TC@MF), demonstrating excellent energy storage and release properties, were synthesized using melamine formaldehyde resin (MF) encapsulated ternary complex consisting of crystal violet lactone (CVL), 2,2-Di-(4-hydroxyphenyl) propane (BPA), and n-hexadecanol. The microstructure, chemical composition, thermal storage capacity, thermal cycling durability, discoloration effect, and thermal regulation performance of TC@MF with different core contents were investigated in detail. With core contents gradually increasing, the chromatic aberration values (ΔE) value of TC@MF increased from 38.23 to 71.69, the melting enthalpy (ΔH m) gradually increased from 180.2 J/g to 218.6 J/g while the leak-proof performance decreased gradually. The TC@MF-2 with the best comprehensive performance has exhibited superior latent heat storage (ΔH m = 192.2 J/g), high chromatic aberration values (ΔE = 57.31), and well leak-proof properties (5.61 %). Furthermore, the thermal performance, morphology, and reversible color reliability of TC@MF-2 remained stable through 100 thermal heating and cooling cycles, demonstrating excellent thermal cycling stability. In summary, such multifunctional microcapsules can directly reflect the energy saturation and depletion states in phase change material applications through color changes. That might be conducive to expanding the value of its practical application in the field of latent heat energy storage, including smart fabrics or fibers, commodity packaging, thermal sensors, reversible thermochromic coatings and solar energy storage, and so on. [Display omitted] [ABSTRACT FROM AUTHOR]