Shape-stabilized phase change materials prepared via mercerization of self-entangled cellulose nanofibrils.

Preparation and application of composite phase change materials stabilized by cellulose nanofibril-based foams for thermal energy storage

Flexible engineering of advanced phase change materials

The establishment of Boron nitride@sodium alginate foam/polyethyleneglycol composite phase change materials with high thermal conductivity, shape stability, and reusability

Novel binary shape-stabilized composite phase change materials (CPCMs) have been successfully prepared using a crosslinked polyurethane (PU) copolymer with a solid–solid phase transition as the supporting framework for loading additional (‘free’) poly(ethylene glycol) (PEG). The PU copolymer was synthesized by a two-step method using 2-hydroxypropyl-β-cyclodextrin (Hp-β-CD) as a chain extender and PEG as a soft segment. The composition, morphology, phase transition behavior and thermal properties of the prepared CPCMs have been elucidated by a wide range of techniques. Investigation of FTIR spectra and SEM images reveal that the ‘free’ PEG and the PU copolymer network within the CPCMs have good compatibility and high affinity due to the noncovalent interactions. Polarized light optical microscopy shows that the CPCMs produce smaller spherulites than pristine PEG, and homogeneous nucleation was prevalent during the crystallization process. Due to the dual-phase transition of the CPCMs (the solid–liquid phase transition of ‘free’ PEG and solid–solid phase transition of the PU matrix) occurring within the same, narrow temperature window, the CPCMs have far higher heat storage density compared with that of traditional shape-stabilized PCMs with the same ‘free’ PEG content. Importantly, thermal cycling and thermogravimetric analyses show that the CPCMs have good reusability and excellent thermal stability for potential use in thermoregulation or energy storage applications.

Solid-liquid phase change materials (PCMs), promising for thermal management, face limited application due to leakage and low thermal conductivity. In this work, a shape-stabilized composite PCM was fabricated using a one-pot in situ process by mixing polyethylene glycol (PEG) with the novel metal-organic network called CFK, which was synthesized from carboxylated multi-walled carbon nanotubes (CMWCNTs), FeCl3, and Kevlar nanofibers (KNFs). The morphology, composition, and thermophysical characteristics of the composite PCM were assessed. Key properties analyzed to validate its performance included leakage rate, thermal conductivity, latent heat, light absorption, photothermal conversion efficiency, and cycling stability. This composite PCM exhibits reduced leakage while maintaining remarkable thermal energy charge/discharge performance. The study establishes that the composite PCM containing 89.9 wt% PEG has a leakage rate of 0.76% since the PEG molecules are deeply embedded in the pores of CFK. The thermal conductivity of this composite PCM was enhanced by 170.5% relative to pure PEG, and the latent heat was measured as 147.9 J·g-1 for fusion and 143.7 J·g-1 for crystallization. Additionally, this composite PCM reveals excellent light absorption capacity, a photothermal conversion efficiency as high as 83.4%, and outstanding stability in photothermal cycling experiments. In short, this work offers a new strategy for both preparing high-performance composite PCMs and applying them in visible light conversion.

An assessment of mixed type PCM-gypsum and shape-stabilized PCM plates in a building for passive solar heating

Ni@rGO into nickel foam for composite polyethylene glycol and erythritol phase change materials

A novel enhancement of shape/thermal stability and energy-storage capacity of phase change materials through the formation of composites with 3D porous (3,6)-connected metal–organic framework

Form-stable paraffin/high density polyethylene composites as solid–liquid phase change material for thermal energy storage: preparation and thermal properties

Investigation of finned heat sinks with PEG-6000/EG and PEG-6000/MWCNT composite phase change material for thermal management application

Thermal performance enhancement of composite phase change materials (PCM) using graphene and carbon nanotubes as additives for the potential application in lithium-ion power battery

Polyethylene glycol (PEG)/hybrid carbon foam (CF) phase change materials (PCMs) were prepared by integrating PEG into CF via dynamic-vacuum impregnation. The hybrid CF was first synthesized by mixtures of graphene oxide (GO) and carbon nanotubes (CNTs) with different volume ratios. The morphologies, chemical structures, thermal conductivities, shape-stabilization levels, and photo-thermal energy conversion levels of these composite PCMs were characterized systematically. The prepared composite PCMs exhibited good shape-stabilization levels and showed their original shapes without any PEG leakage. It was found that the polyethylene glycol/carbon foam with multi-walled carbon nanotubes (PEG/MCF) composite PCMs had a better shape-stable performance below the temperature of 250 °C, and the thermal conductivity of the PEG/MCF composite PCMs reached as high as 1.535 W/(mK), which was obviously higher than that of polyethylene glycol/carbon foam with single-walled carbon nanotubes (PEG/SCF, 1.159 W/(mK)). The results of the photo-thermal simulation tests showed that the composite PCMs had the ability to absorb light energy and then convert it to thermal energy, and the maximum thermal energy storage efficiency of the PEG/MCF composite PCMs and the PEG/SCF composite PCMs was 92.1% and 90.6%, respectively. It was considered that a valuable technique to produce high-performance composite PCMs was developed.

Preparation and characterization of a solar-driven sodium acetate trihydrate composite phase change material with Ti4O7 particles

A novel biogenic porous core/shell-based shape-stabilized phase change material for building energy saving

Light-actuated shape memory and self-healing phase change composites supported by MXene/waterborne polyurethane aerogel for superior solar-thermal energy storage