Phase Change Material Research Articles (Page 1)

Abstract Enhancing thermal performance in phase change materials (PCMs) is critical for advancing thermal energy storage systems. Passive strategies, such as optimizing geometry and using nanoparticles, offer promising ways to enhance heat transfer and energy efficiency. This study examines a flow of non-Newtonian Casson nanofluid synthesized by sodium sulfate decahydrate PCM, water, borax stabilizer, and aluminum oxide (Al₂O₃) nanoparticles subjected to an external magnetic field in an optimized octagonal cavity with plus-shaped fin. Octagonal cavity is heated from below; the remaining walls of the enclosure are thermally insulated. The governing equations are solved numerically using the Finite Element Method (FEM). Simulations explored the effects of the Casson parameter β, Rayleigh number Ra, and Hartmann number Ha Casson on flow structure, Nusselt number (Nu), and mass Sherwood number (Sh). Results show β and Ha have competing influences. Lower β enhanced convection, raising the mean Nusselt number by ∼55% versus large β, while high Ha suppressed flow and heat transfer. Ra was the dominant factor and increasing Ra shifted the system to convection-dominated regime, strengthening vortices and significantly improving thermal (Nu) and solute (Sh) transfer.

Solar thermal energy plays a vital role among renewable energy sources, with enhancing solar collector performance remaining a key research priority. This study investigates the efficiency improvement of a mini-channel flat plate collector integrated with a novel composite phase change material (CPCM), Pb(NO3)2 -NaNO3 -NaCl/Boron Nitride. The incorporation of CPCM effectively minimizes heat loss, stores surplus thermal energy, and provides passive cooling to the collector. Experimental results revealed that the collector outlet temperature decreased from 62°C to 52°C, resulting in a thermal efficiency of 90%. The maximum power output reached 400 W, while the system stored 50 kJ of thermal energy. The CPCM exhibited a melting temperature of 110°C and a solidification temperature of 115°C, maintaining stability with only a 2°C variation after multiple thermal cycles. Thermogravimetric analysis confirmed excellent stability with 40% degradation at 700°C. Furthermore, the CPCM demonstrated a thermal conductivity of 0.92 W/m ċ K, a latent heat of 12.53 J/g, and a specific heat capacity of 0.64 J/g ċ K. The mini-channel configuration enhanced heat flux by 30% with a pressure drop of 100 Pa at 6 L/min flow rate. CFD simulations conducted using Python verified that CPCM integration and the mini-channel design substantially improved collector performance.

Thermoanalytical and Physical Characterization of Animal Fat and Commercial Organic Phase Change Materials

Chalcogenide phase-change materials exhibit large, reversible index shifts that promise nonvolatile, energy-efficient photonic technologies. Yet, current implementations either rely on ultrathin, lossy films integrated with passive Si/SiN waveguides, limiting index modulation, or exploit direct laser writing for localized switching, at the expense of strong optical confinement. Here we demonstrate an antimony trisulfide (Sb 2 S 3 ) waveguide platform where the material itself forms the guiding core. The proposed architecture theoretically supports substantial modulation of both effective index and absorption, thereby providing a robust platform for the realization of reconfigurable and densely integrated photonic devices.

Review of Micro/Nanoencapsulated Phase-Change Materials for Thermal Energy Storage in Moderate Thermal Environments

Personal thermal management (PTM) systems are pivotal for energy-efficient thermal regulation. However, conventional phase change fibers (PCFs) are limited by insufficient latent heat capacity and phase change materials (PCMs) leakage. To address these challenges, we encapsulated polyethylene glycol (PEG) as a phase change material within a continuous carbon nanotubes (CNTs) network by coagulation bath solvent regulation. After optimizing the CNTs network contraction effect by controlling the ethanol (EtOH)/water content ratio, the resultant PEG/CNTFs(50wt%EtOH) (obtained from a 50 wt % EtOH coagulation bath) synchronously demonstrated a series of attractive features, including a high phase change enthalpy (145.2 J/g), robust tensile strength (487.0 MPa), and outstanding thermal conductivity (59.3 W·m-1·K-1). The interlaced CNTs architecture endows the fibers with acceptable electrical conductivity (0.62 MS/m), enabling dual-mode thermal regulation by combining passive phase change buffering with active Joule heating. Additionally, the material exhibited high cycling stability, retaining 99.4% of its enthalpy after 500 thermal cycles. Their distinct flexibility and mechanical strength allow them to be woven into large textiles (e.g., 30 cm × 150 cm), highlighting their suitability for wearable PTM applications with combined Joule heating and phase-change buffering. This scalable, one-step fabrication strategy synergizes high energy density, structural resilience, and multifunctionality, positioning PEG/CNTFs as a transformative solution for next-generation smart textiles.

α-synuclein-stabilized nanocarriers (α-Syn NCs) have been developed as a functional drug delivery platform exhibiting a facilitated intracellular delivery of drugs and their light-triggered induced release via heat generation, which could exert both chemical and physical therapeutic effects on cancer cells. To achieve this, a eutectic phase-changing material (PCM) composed of lauric and myristic acids was used as the core to encapsulate both chemical drug and near-infrared (NIR) absorbing dye by employing an oil-in-water emulsification procedure. α-Syn, an intrinsically disordered protein with self-assembly properties, served as a stabilizer at the oil-water interface by forming a structurally stable shell around the PCM core. The resulting α-Syn NCs exhibited physicochemical stability under various conditions including changes in pH, ionic strength, and mechanical stress. Notably, the α-helix induced on the surface of α-Syn NC facilitated membrane penetration of the nanocarrier, which would contribute to an efficient intracellular drug delivery. Upon NIR laser irradiation, the photothermal effect of the NIR-absorbing dye allowed the PCM core to melt, enabling controlled drug release. Simultaneously, the localized heat also caused the death of cancer cells, and the combined action of thermal damage and chemotherapeutic drug release demonstrated a potential of α-Syn NCs to be utilized for combinatorial therapy. This integrated system, therefore, offers a distinctive therapeutic strategy toward cancer by exerting both chemical and physical therapeutic effects with the α-Syn-stabilized nanocarrier capable of facilitating membrane translocation and an externally triggered drug release.

This study analyzes the hydrodynamic and thermal behavior of a power-law nanofluid containing nano-encapsulated phase change materials (NEPCMs) over a non-isothermal stretching sheet. The combined effects of non-Newtonian rheology and latent heat transport due to NEPCM inclusions are formulated through boundary-layer theory and the power-law constitutive relation.The resulting nonlinear similarity equations are solved numerically using the shooting technique with Runge–Kutta integration. Results indicate that embedding NEPCM particles within the power-law nanofluid significantly enhances heat transfer through latent heat absorption and release, though it also increases wall shear stress. Higher power-law indices suppress velocity and temperature distributions, mitigating this shear enhancement. These findings reveal a competing interaction between fluid rheology and the thermal storage capacity of NEPCMs. The study offers new insights into the coupled flow and heat transfer mechanisms of NEPCM-suspended power-law nanofluids, with relevance to advanced cooling, polymer processing, and energy storage applications.

Heat dissipation of lithium‐ion cells during its operation is critical for its performance. This study investigates the thermal behavior of a Li‐ion battery module (7.8 Ah, 11.1 V) under varying discharge rates (C‐rate) (0.91 to 1.45C) using experimental and numerical methods. Under natural convection at 1.45C C‐rate and 27°C ambient temperature, the module reaches 55.2°C, exceeding safe operational limits. Forced convection (FC) with inlet velocities of 0.4 and 0.7 ms −1 reduces the temperature to 40.8 and 37.7°C, respectively, though it causes temperature nonuniformity. To address these limitations, passive cooling with phase change material (PCM) was explored. PCM lowered the maximum temperature to 39.8°C with improved temperature uniformity (Δ T = 3.1°C). Further enhancement using expanded graphite increased PCM's thermal conductivity, maintaining low and uniform temperatures. Numerical simulations, validated against experimental results, were conducted to analyze heat transfer mechanisms under extreme C‐rates up to 5C and hot ambient temperatures up to 45°C. The findings demonstrate that while FC effectively cools lithium‐ion modules, it may reduce cell performance due to uneven temperature distribution. In contrast, PCM‐based passive cooling offers better temperature uniformity, though it is limited by low thermal conductivity, which can be mitigated by incorporating EG.

Abstract Exploiting the heat energy storage capability of phase change materials is emerging as a potential new strategy for managing Li-ion cell temperature changes during cycling that is both lighter and more energy efficient than active battery thermal management systems. Micro-encapsulated octadecane (C18H38) comprising of a carbon composite-based shell (carbon nanotubes and graphene oxide) selected to maintain a temperature of 27 °C was formulated into a coating and applied onto the exterior of 18650, 1.6 Ah LiFePO4|graphite cells. The coating delivered a heat storage capacity of 100 J·g-1, and thermal imaging showed that the average peak increases in cell temperature during galvanostatic cycling was reduced by 7 °C when the coating was applied. The optimum coating thickness was found to be 3 mm, increasing the cell mass by 10-15%. Furthermore, the coatings delivered a cell temperature reduction of 4 °C during a modified European drive cycle, highlighting good functionality towards practical cell usage.

Thermoresponsive structural color materials hold great promise for dynamic anti-counterfeiting and thermal monitoring, yet their widespread adoption is hindered by complex self-assembly processes and limited scalability. Here, an innovative interfacial fusion-separation mechanism is proposed for programmable thermochromic coatings (HPTCs), achieved by blending independently chromogenic hollow silica (H-SiO2) photonic nanopigments with eutectic phase change material (EPCM). This design circumvents traditional self-assembly requirements while enabling commercially viable spray-coating fabrication. Meanwhile, these HPTCs exhibit tunable transition thresholds rapid color switching (4 s) and exceptional cycling stability (>500 cycles) within a narrow physiological temperature window (33-37 °C), driven by EPCM solid-liquid transitions modulating refractive-index contrast. A sandwich-like process, comprising waterborne acrylic (WA) adhesive, H-SiO2-EPCM functional, and WA protective layers, simultaneously ensures mechanical robustness and substrate versatility. The self-assembly-free design enables standalone anticounterfeiting labels with programmable color patterns for interactive authentication. Furthermore, the fusion-separation-driven thermochromic mechanism enables programmable tuning of response temperatures via fatty acid selection, allowing integration of multiple HPTCs into a versatile real-time temperature indicator for personalized health monitoring, drinking-water temperature warning, and electronic thermal risk detection. This interfacial engineering strategy simplifies fabrication of stimuli-responsive optical materials, demonstrating significant potential for scalable manufacturing of commercial anticounterfeiting labels and the temperature indicator.

In addition to conventional doping strategies, nano-structuring combined with interfacial engineering has recently emerged as a promising approach for enhancing phase-change material (PCM) performance. In this work, we comparatively investigate anomalous crystallization kinetics in two-dimensional (2D) confined Ge2Sb2Te5 (GST), GeTe, and Sb2Te3 nano-films using flash differential scanning calorimetry, with tungsten (W) serving as the confining layer. We observe that both GST and GeTe nano-films exhibit distinct fragile-to-strong crossover (FSC) behavior under 2D confinement, while Sb2Te3 shows no FSC regardless of confinement. The presence of FSC behavior helps alleviate the trade-off between fast crystallization near the melting temperature and high thermal stability near the glass transition temperature. Time–temperature–transformation curves reveal that 2D confined GST achieves crystallization in only 3.4 ns at 680 K, outperforming GeTe (17 ns at 626 K) and Sb2Te3 (257 ns at 668 K). The occurrence or absence of FSC is attributed to interfacial bonding differences, i.e., strong W–Ge bonds promote FSC, whereas weak W–Te and/or W–Sb interactions do not. These results highlight the role of interface-engineered 2D confinement in tailoring PCM crystallization kinetics, offering perspectives for advanced memory applications.

Photo-responsive microencapsulated phase-change materials (MEPCMs) are attracting growing interest for their significant potential in solar energy applications and advanced intelligent thermal management systems, owing to their exceptional capacity for thermal energy storage, efficiency for photothermal conversion, and capability for multifunctional integration. This review provides a systematic summary of the advancements in photo-responsive MEPCMs containing photothermal, photocatalytic, and luminescent materials in the past five years, highlighting their potential in energy conversion, pollutant degradation, and intelligent sensing applications. Moreover, perspectives for future research are provided to enhance the practical application of photo-responsive MEPCMs.

Thermal energy, encompassing both heating and cooling demands, accounts for the largest share of global energy consumption. Harvesting thermal energy from the environment, including the Sun and darkness, holds promise for decarbonizing thermal sectors, but suffers from low efficiency and intermittency. Here, inspired by ginkgo leaves featuring wax-coated vertical palisade cells, a 24-h bidirectional thermal energy harvesting approach is developed by integrating spectrally selective aerogels with anisotropic composite phase change materials (CPCMs). During daytime, sunlight is captured, converted into heat, and stored in anisotropic CPCMs with high axial thermal conductivity (24.16 W·m-1·K-1) and an anisotropy ratio of 3.7. Under one-sun irradiation, a high solar thermal energy storage efficiency of 87.5% with a peak temperature of 382.3 K is achieved by leveraging spectrally selective aerogels exhibiting "greenhouse effects". At night, a maximum radiative cooling power of 118.8 W·m-2 is attained, enabling cold energy storage at a temperature 4.0 K below ambient. The proposed leaf-inspired device operates continuously over 24 h, delivering annual thermal energy savings of 5321.4 MJ·m-2·yr-1, outperforming standalone solar thermal and radiative cooling systems by 44.8% and 223.3%, respectively. This bioinspired bidirectional energy harvesting strategy employing both solar and outer space resources, establishes a promising approach toward a carbon-neutral thermal energy supply.

Introduction: The invention of a lunch box with phase-change materials incorporated to keep food warm throughout work hours is the subject of this paper. Since harmful chemicals render the food unfit for consumption when they come into contact with it, the choice of phase change material is essential. Method: Adopting a healthy lifestyle now includes carrying electronic lunch boxes and ordering takeaways. Nevertheless, utilizing the electric lunch box at work is a bother. Therefore, this study discusses a prototype of a lunch box that has been created and can keep food warm after it has been packed at home for 4-5 hours. The method of preparing the PCM FS65 is discussed and its stability over thermal cycling is analyzed. objective: To synthesize phase change material composite which does not go into liquid state in melting cycle. To understand the thermal stability of the phase change material composite To prove the efficacy of the composite in lunch box for keeping the food warm Result: The thermal resistance of the insulating materials and the quantity of PCM are the two design considerations for the lunch box that have been covered in this study. To explore these, a warm food criterion at a temperature of 45°C has been used. Conclusion: This research article has discussed the ideal PCM weight required for a 5-hour retention time as well as the ideal insulating material to make the least bulky lunch box design.

Crystallisation, dissolution and diffusion in a Solid-Metal in Liquid-Metal colloidal system.

Discarded sericultural mulberry branch based triple layer composite phase change material with lignin enhanced thermal management capability.

Recyclable cellulose nanofiber/carbon nanotube frameworks encapsulating thermoresponsive organogels for high-energy-density shape-stabilized phase-change composites.

Experimental study of thermal convection and melting dynamics in a Phase Change Material (PCM) embedded in a solid foam

Optimizing chip thermal management performance in microchannel heat sinks driven by the synergistic effect of liquid cooling and phase change materials