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Thermal energy storage and utilization has been widely concerned due to the intermittency, renewability, and economy of renewable energy. In this paper, the potential energy function of binary Na2CO3–K2CO3 salt was first constructed using the Deep Potential GENerator (DPGEN) enhanced sampling method. Deep potential molecular dynamics simulations were performed to calculate the thermal properties and structural evolution of binary carbonates. The results show that as the temperature increases from 1073 to 1273 K, the viscosity and thermal conductivity decrease from 5.011 mPa s and 0.502 W/(m K) to 2.526 mPa s and 0.481 W/(m K), respectively. The decrease in viscosity is related to the distance and interaction between the molten salt ions. In addition, the diffusion coefficients, energy barriers, ionic radius, angular distribution function, and coordination number of molten salt were calculated and analyzed. The CO32− exhibits a stable planar triangular structure. The ionic radius of Na+ is smaller than that of K+, which makes Na+ suffer less spatial hindrance during motion and has a higher diffusion coefficient. The energy barriers that Na+ needs to overcome to escape the Coulomb force is greater than that of K+ ions, so molten salt containing Na+ may possess greater heat storage potential. We believe that the potential function constructed with DPGEN enhanced sampling strategy can provide more convincing results for predicting the thermal properties of molten salts. This paper aims to provide a technical route to develop the novel complex molten salt phase change material for thermal energy storage. [ABSTRACT FROM AUTHOR]

Utilizing thermochemical reactions for thermal energy storage and solar fuel production has been an emerging research topic. Thermal transport properties of the materials are an important parameter that can determine the kinetics and efficiency of thermochemical reactions. With the increasing number of new thermochemical materials (TCMs); however, there is a lack of reliable techniques to monitor the thermal transport property of the materials and their changes as a function of reactions in real time. In this work, we report the in situ monitoring of thermochemical reactions using modulated photothermal radiometry (MPR). The thermal conductivities of two TCMs, namely, calcium hydroxide (Ca(OH)2) and Ba0.15Sr0.85FeO3−δ (BSF1585), were measured as a function of temperature and time using the MPR technique. The measured thermal conductivities were correlated to the reaction. The work has two significant contributions to the research communities. First, it provides a non-invasive diagnostic tool for monitoring the thermal transport properties of TCMs that can potentially be a high-throughput measurement technique conducive to optimizing TCMs, reactors, and related thermal systems. Second, for TCMs that show observable changes in thermal transport properties, a correlation between the measured thermal conductivity and the conversion fraction of the reaction can be established for monitoring the reaction kinetics based on thermal characterization. [ABSTRACT FROM AUTHOR]

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Syntactic foams are lightweight porous composites obtained by the addition of hollow glass microspheres (HGMs) to a polymer matrix. This work experimentally and numerically investigates the thermal behavior of epoxy‐based syntactic foams with enhanced multifunctionality produced by incorporating microencapsulated phase change materials (PCMs) as functional fillers, providing thermal energy storage and temperature stabilization due to its large latent heat of melting. Foams are fabricated using varying ratios of HGMs (0–40 vol%) and PCM (0–40 vol%) to achieve tuned densities and thermal properties with a total filler content of up to 40 vol%. A one‐dimensional numerical heat transfer model based on the enthalpy method is presented to simulate the thermal behavior of these materials. The model accurately incorporates the specific heat and thermal conductivity of the foam components, as well as the latent heat absorption during PCM melting (up to 68 J/g). The model is experimentally validated by demonstrating good agreement with the measurements of transient temperature profiles during heating tests on the foam samples. The validated tool is then leveraged to model the thermal response of the foams under a sinusoidally varying heat source, similar to the possible real applicative scenarios. These results can help optimize foam compositions balancing energy storage density, heat transfer properties, and structural support for lightweight energy storage systems. Potential applications include high‐efficiency thermal management in battery packs, electronic cooling, solar energy storage, and sustainable temperature‐controlled buildings. Highlights: Foams with 0–40 vol% PCM and 0–40 vol% HGM show up to 68 J/g latent heat.1D numerical model accurately captures thermal conductivity and PCM phase change.Validated model simulates thermal response under sinusoidal heat, optimizing foam composition.Foams act as thermal reservoirs, maintaining up to 5°C lower surface temperatures than epoxy. [ABSTRACT FROM AUTHOR]

Solar-thermal energy storage (STES) within solid-liquid phase change materials (PCMs) has emerged as an attractive solution to overcome intermittency of renewable energy. However, current storage systems usually suffer from slow charging rates, sacrificed storage capacity, and overheating tendency. Inspired by the thermoregulation behavior of Cyprinid fish, here, we present a quick-responsive, ultrafast, large-capacity, overheating-protective STES strategy. We fabricate a liquid-infused solar-absorbing foam charger that can rapidly advance the receding solid-liquid charging interface to efficiently store solar-thermal energy as latent heat and spontaneously float upward to cease the charging process upon overheating. This bioinspired dynamic charging is adaptable to a variety of PCMs, unlocking the potential for safe and efficient utilization of renewable thermal energy. [ABSTRACT FROM AUTHOR]

Introduction: Solar resources are rich in north China and however, solar thermal energy has little contribution to space heating due to the intermittency and instability as well as the lack of seasonal energy storage technology. Although underground thermal energy storage (UTES) can solve the above problems effectively, the existing UTES systems either have low energy storage density and recovery efficiency or have high construction cost. Methods: Inspired by the enhanced geothermal system (EGS), here a novel scheme of storing high temperature thermal energy into the shallow depth EGS (SDEGS) is proposed. Thermal energy is stored into SDEGS during the non-heating season and is extracted for space heating during the heating season. Results: The results show the thermal performance of SDEGS always remains stable due to continuous thermal energy injection, and its thermal recovery efficiency is always greater than 90% by storing thermal energy into the tight rocks and circumventing the formation of the natural convection. Discussion: SDEGS can be constructed in the shallow buried depth rocks having a low requirement about temperature, largely reducing project cost and risk and widening the application range. [ABSTRACT FROM AUTHOR]

In high-temperature mines, miners are exposed to high temperatures for long, increasing body temperature and causing diseases such as heatstroke. Therefore, adjusting the environmental parameters of the working face has become the key to managing thermal stress. Based on the binary method, the predicted thermal strain model (PHS) was transformed into a computer program to determine the zero inflection point of human body heat storage. When workers’ body heat storage reached the zero inflection point, changes in working face temperature, wind speed, and physiological parameters were analyzed under different labor intensities. The results indicate that the higher the labor intensity, the higher the air humidity, and the lower the working face environment temperature that maintains zero heat storage for the human body. A wind speed of 2.5 m/s is optimal for maintaining zero heat storage for the human body. When the wind speed is too high or too low, the working surface environment temperature required to maintain zero heat storage for the human body is relatively low. A thermal stress control method was proposed based on research, providing a reference for adjusting wind speed and refrigeration equipment in high-temperature mining working faces. [ABSTRACT FROM AUTHOR]

The building sector is a significant contributor to global energy consumption, necessitating the development of innovative materials to improve energy efficiency and sustainability. Phase change material (PCM)-enhanced concrete offers a promising solution by enhancing thermal energy storage (TES) and reducing energy demands for heating and cooling in buildings. However, challenges related to PCM leakage, mechanical strength reduction, and encapsulation durability hinder widespread adoption. This paper critically reviews the various PCM incorporation techniques and evaluates their impact on thermal performance and structural integrity. Our findings revealed that while PCM integration improves thermal efficiency, it reduces mechanical strength, especially at higher PCM content. To address these challenges, recent work emphasizes advancements in encapsulation technologies and thermal property optimization, focusing on mitigating leakage and enhancing durability. Organic PCM types are favored for concrete applications due to their compatibility, though issues with leakage control and strength retention remain unresolved. Hence, the choice of incorporation technique must balance application requirements, allowable mechanical property reductions, and cost constraints. Moreover, the lack of standardized methods to assess long-term PCM-composite durability highlights a need for further development of PCM encapsulation and integration techniques to optimize thermal and structural performance. [ABSTRACT FROM AUTHOR]

To cope with the uncertainty brought by the large-scale integration of renewable energy under the goal of carbon neutrality, it is necessary to tap and utilize flexible and adjustable resources from both the source and the load side at the same time. Hence, a flexible low-carbon optimal scheduling method for distribution networks is proposed in this paper, which takes into account the participation of heat storage industrial loads in demand response. Firstly, the model of the gas turbine equipped with a flexible carbon capture device is established, and the non-convex constraint introduced by the adjustable flue gas diversion ratio is convexified. Then the model of the fused magnesium load, a representative of heat storage industrial loads, is established for its participation in demand response. The segment linearization and convexification methods are performed on the conditional productivity constraints of the fused magnesium load. On this basis, a mixed-integer linear programming model for flexible and low-carbon optimal dispatch of the distribution network is developed by using the stochastic optimization theory and solved by commercial solvers. The proposed method is verified to be able to ensure the economic operation of the distribution network while reducing carbon emissions and promoting renewable energy consumption. [ABSTRACT FROM AUTHOR]

Organic phase change materials (O-PCMs) such as alkanes, fatty acids, and polyols have recently attracted enormous attention for thermal energy storage (TES) due to availability in a wide range of temperatures and high latent heat values. However, low thermal conductivity and leakage problems during the phase transition of O-PCMs are of great concern. To overcome the long-standing drawbacks of O-PCMs, we critically discussed the preparation techniques of macro encapsulation phase change (MaPCM), microencapsulation phase change materials (MPCM), shape stabilized phase change materials (SSPCM), eutectic phase change materials (EPCM), nano-enhanced phase change materials (NePCM) along with the morphological insights, thermal property enhancements & molecular dynamics (MD) simulation of the prepared composite PCMs. The article also discusses fundamental thermal property increments in phonon interaction, Van der Waals forces of attraction, aspect ratio, thermal conductive path, temperature agglomeration, surfactant effect, and thermal resistance of O-PCMs. The current ongoing review manuscript consolidates the variation in thermal properties with different concentrations of nanoparticles, considering the variety of references to provide valuable insight to the researchers. Carbon-based nanoparticles dispersed with the O-PCMs are the best way to reduce the low thermal conductivity problem. The π-π stack interaction between the O-PCMs and the nanoparticles decreased the leakage problems of O-PCMs during encapsulation and shape stabilization. The authors observed that the highest increment in the thermal conductivity and the latent heat of the OPCMs is 1008.33% and 60%, respectively. Finally, the present review provides a new vision and draws more attention to the material reliability of O-PCMs-based applications in the future, particularly regarding TES. [ABSTRACT FROM AUTHOR]

Thermal storage systems are needed to overcome solar intermittency and make this energy source more flexible and competitive for concentrated solar power plants. Single-tank sensible heat storage using both fluids and materials is a promising option for reducing storage costs and promoting the development of concentrated solar power. This work is a thorough review on the parameters influencing the performance of a dual-medium thermocline storage system for concentrated solar power plants. Thus, indicators such as efficiency, utilisation rate, thermocline thickness and energy efficiency of the storage system are presented in order to quantify the performance of the system. In addition, the impact of geometric and operating parameters on the performance of the thermocline storage system has been discussed. [ABSTRACT FROM AUTHOR]

Thermal systems, including those utilising solar energy and waste heat recovery, often have a mismatch between the energy supply and demand. It is crucial to implement a form of Thermal Energy Storage (TES) to effectively utilise the energy source. This study evaluates the thermal performance of a packed bed Latent Heat Thermal Energy Storage (LHTES) unit that is incorporated with a solar flat plate collector. The results show that the time required to charge the tank is reduced by 7% when the porosity is increased from 0.49 to 0.61, and also when the flow rate is raised from 2 to 4 kg/min, the charging time decreases by 2.5%. Additionally, studies were done to investigate the performances of different kinds of paraffin (RT30, RT28HC, WAX, RT58, and P56-58), and compare the heat capacities of each TES tank which resulted in the RT58 TES tank having the highest heat capacity. Abbreviations: BC: boundary conditions; HTF: heat transfer fluid; LHS: latent heat storage; LHTES: latent heat thermal energy storage; PCM: phase change material; SHS: sensible heat storage; TES: thermal energy storage [ABSTRACT FROM AUTHOR]

Phase-change materials (PCMs) with three-dimensional thermally conductive skeletons show promise for thermal energy storage, but they have poor stability. Therefore, based on hydrogen bonding between graphene oxide and polyvinyl alcohol, a shape-stable thermally conductive graphene oxide/graphene nanoplates/polyvinyl alcohol (GO/GNP/PVAs) 3D porous skeleton was prepared by a simple vacuum freeze–drying method in this paper. To further improve the thermal conductivity of the GO/GNP/PVAs 3D porous skeleton, so carbonization is applied on it. After encapsulating polyethylene glycol (PEG) in the skeleton, a thermally conductive phase-change composite with good shape stability was obtained, even at a PEG loading as high as 96.1%. The carbonized C-GO/GNP/PVAs/PEG phase-change composites exhibited higher thermal conductivity (1.57 W m−1 K−1) than uncarbonized GO/GNP/PVAs/PEG phase-change composites (0.52 W m−1 K−1). This was mainly due to the low thermal conductivity GO annealing into high thermal conductivity reduced graphene oxide (rGO), which formed a conductive three-dimensional network. Meanwhile, the formation of a carbon skeleton by PVA chains after annealing also improved the thermal conductivity of the composites. The C-GO/GNP/PVAs/PEG phase-change composites also showed excellent solar-to-heat conversion properties. [ABSTRACT FROM AUTHOR]

Phase change materials (PCMs) exhibit a promising application as a heat storage medium in battery thermal management. However, the flammability, low thermal conductivity, and leakage problems of organic PCMs constrain the development. In this study, a novel strategy based on inorganic hydrated salt with natural nonflammability was proposed. Sodium acetate trihydrate and disodium hydrogen phosphate dodecahydrate composite materials (SAT-DSP) were synthesized without affecting the properties. The prepared SD@SiO2 with sodium silicate as the precursor, while SAT-DSP as the core material, possessed the dual heat storage performance of phase transition and thermochemical heat storage. The SiO2 shell with a dense surface successfully realized the encapsulation of SAT-DSP, and the combined effect of heterogeneous nucleation and mesoporous confinement effectively inhibited the phase separation of phase change materials. The optimal ratio of SD@SiO2 was determined through a comprehensive analysis of morphology, thermal stability, and thermal storage properties. The heat storage density was up to 509.18 J g−1 with a phase transition temperature of 78.78 °C. It improved the chemical instability and leakage of hydrated salts and centralized the dehydration process of SAT-DSP to achieve rapid response. Even after continuous heating on a 120 °C heating platform for 30 min, the surface temperature of SD@SiO2 was maintained within a safe range (< 65 °C). This inorganic phase change material exhibited considerable potential for application in battery thermal runaway protection. [ABSTRACT FROM AUTHOR]

This research investigates methods to enhance the efficiency of solar ponds as sustainable energy storage systems by leveraging phase change materials (PCMs) and nanoparticles. Solar ponds often suffer from reduced performance during hot summer months due to high temperatures, which limit their overall efficiency. This study focuses on the impact of adding candle soot-derived carbon nanoparticles at different mass fractions (1 mass%, 2 mass%, and 3 mass%) on the thermal performance, storage capacity, and efficiency of solar ponds. Conducted over a seventy-five-day experimental period, the study reveals that the average temperature of the lower convective zone (LCZ) increased by 15.3% with the use of PCM and by 28.3% with the addition of PCM containing 2 mass% carbon soot, compared to traditional solar ponds. The incorporation of paraffin wax and carbon soot significantly improves energy storage capacity, enhances thermal efficiency, and reduces convection losses. These findings demonstrate that PCMs combined with candle soot nanoparticles can effectively enhance the efficiency and performance of solar ponds, offering a promising approach for optimizing solar energy storage systems. [ABSTRACT FROM AUTHOR]

In order to improve the utilization rate of solar energy, a new type of photo-thermal phase-change microcapsules PCM@SA@PDA was successfully prepared with n-docosane (C-22) as core material and sodium alginate (SA) and polydopamine (PDA) as composite wall material. Here, SA capsules were formed by cross-linking of metal ions to envelop and prevent the leakage of melted C-22 (PCM@SA). Dopamine was self-polymerized on the surface of PCM@SA microcapsule; thus, efficient light absorption was achieved for photo-thermal transformation. The chemical structure, thermal properties, light absorption properties and photo-thermal conversion properties of the prepared microcapsules were analyzed and characterized. Based on the study of the effect of different contents of C-22 core materials on the thermal storage performance of PCM@SA, the optimal addition amount of C-22 was determined to prepare photo-thermal phase-change microcapsules. Compared with the PCM@SA, the photo-thermal phase-change microcapsule PCM@SA@PDA still showed good stability and heat storage performance. Their melting heat enthalpy was about 152.5 J g−1, and they also showed better photo-thermal conversion performance. Combining C-22, SA and PDA to prepare photo-thermal conversion phase change energy storage materials, the method was characterized by strong adaptability, simple operation, low production cost and high economic benefits, which could not only further improve the stability of the composite material, but also increase the photo-thermal conversion efficiency of the system. Therefore, this composite material integrating active light absorption, conversion and storage functions would have higher solar energy utilization rate and broader application prospect. [ABSTRACT FROM AUTHOR]

This work aims to improve the efficacy of phase change material (PCM)-based shell-and-tube-type latent heat thermal energy storage (LHTES) systems utilizing differently shaped fins. The PCM-based thermal process faces hindrances due to the lesser thermal conducting property of PCM. To address this issue, the present problem is formulated by adopting the concept of conducting fins. The geometry comprises concentric cylinders, in which the inner cylinder carries the heat transfer fluid (HTF), whereas the outer cylinder contains PCM. Four number fins of different shapes are attached outside the HTF carrying cylinder. The enthalpy–porosity approach is used for modeling the phase change and heat transfer. The investigation is conducted numerically utilizing the finite volume-based numerical technique for the range of control variables such as the shape of the fins (straight, curved, and wavy fins) and various temperatures of the HTF. Furthermore, all the results are assessed with the results of no-fin case. The results show that the melting time drops markedly by 122.2% using a curved fin. This paper shows the capability of geometry modification in enhancing the heat energy storage rate of thermal energy storage systems. The PCM-based latent heat thermal energy storage (LHTES) unit is very effective for sustainable energy solutions through storing and releasing of renewable energy following the supply and demand cycle. Therefore, the outcome of the present study will enrich the knowledge on the design of efficient and compact thermal energy storage systems. [ABSTRACT FROM AUTHOR]

There is an increasing need for sustainable solar thermal energy systems for power production, desalination, cooling and heating, and even cooking in the current world. The most significant challenge for the further development of solar-based technology is the discontinuity and lack of solar irradiance, especially on cloudy days and night hours. Thermal energy storage is the most suggested technology to tackle this challenge partly or mostly. Phase change materials can have a notable role as thermal energy storage in solar thermal energy systems. Besides, parabolic dish collectors are a type of solar collector technology that can be utilized in various thermal systems due to their high concentration ratio and working temperatures. Hence, in this review, the applications of phase change materials in various solar parabolic dish collectors will be investigated in detail. Moreover, the research works are divided into five main categories: power production systems, cooling-heating systems, desalination systems, solar cooker systems, and multigeneration systems. Based on the literature, studies of phase change material's applications in dish collectors are currently limited to theoretical studies in several cases. There is vast research need for further experimental investigations in all the mentioned categories. To this end, some concluding points and suggestions for future studies will be presented to the researchers. [ABSTRACT FROM AUTHOR]

Inorganic hydrated salts, noted for their high thermal storage density, excellent thermal conductivity, and non‐toxicity, are suitable candidate material for thermal management, particularly in enhancing human living environments when their phase transition points are near room temperature. Herein, we present an efficient and environmentally friendly microencapsulation method for inorganic hydrated salt through organic phase separation method. Eutectic hydrated salt (EHS) consisted of sodium carbonate decahydrate (SCD) and disodium hydrogen phosphate dodecahydrate (DHPD) was prepared as the core material while the mixture of ethyl cellulose (EC) and acrylonitrile‐butadiene‐styrene (ABS) as composite shell materials. Various characterization techniques were used to evaluate the micromorphology, chemical structure, thermal properties and thermal stability of the microcapsules. The resulting microcapsules exhibited a phase change temperature of 22.6 °C with a remarkable enthalpy of 131.4 J/g. Particularly, the enthalpy remained at 117.7 J/g even after 50 thermal cycles, indicating stable cycling thermal reliability. Furthermore, it was confirmed that the EHS was effectively encapsulated within the composite shell, and the microcapsules had a quasi‐spherical shape and core‐shell structure. More importantly, this method of microencapsulation could potentially be extended to other liquid hydrated salts at room temperature, offering a versatile approach for future applications. [ABSTRACT FROM AUTHOR]

We compared two methods of partitional calorimetry to calculate heat storage and heat debt during cold air (0°C) exposure causing mild core cooling. Twelve participants performed a 5 min baseline in thermoneutral conditions (∼22.0°C, ∼50% relative humidity) followed by cold air exposure (∼0°C) until rectal temperature was reduced by ∆−0.5°C. Partitional calorimetry was used to calculate avenues of heat exchange (radiative, convective, and evaporative), heat storage, and heat debt continuously throughout cold exposure. We compared deriving these variables using prediction equations based on environmental and participant characteristics (PCALEquation Method) versus using measurement tools such as humidity sensors and heat flux discs (PCALHeat Flux Method). There were significant differences between methods (all p ≤ 0.001) for determining heat exchange, heat storage, and heat debt. At ∆−0.5°C, PCALHeat Flux Method had greater levels of radiative and convective heat exchange (PCALHeat Flux Method: −143.0 ± 16.8 W∙m2 vs PCALEquation Method: −123.0 ± 12.9 W∙m2, p ≤ 0.001), evaporative heat exchange (PCALHeat Flux Method: −9.0 ± 1.7 W∙m2 vs PCALEquation Method: −4.1 ± 0.0 W∙m2, p ≤ 0.001), heat storage (PCALHeat Flux Method: −15.0 ± 31.0 W∙m2 vs PCALEquation Method: +6.0 ± 25.9 W∙m2, p = 0.020), and heat debt (PCALHeat Flux Method: −692.0 ± 315.0 kJ vs PCALEquation Method: −422.0 ± 136.0 kJ, p ≤ 0.001). Overall, this study found the largest discrepancies between the two methods were when the environmental conditions and skin temperature were in high flux, as well as when core temperature was reduced by ∆−0.5°C. The use of PCALHeat Flux Method may be more advantageous to use in the cold to provide a higher resolution measurement of cold strain. [ABSTRACT FROM AUTHOR]

Wet bulb globe temperature (WBGT) is a commonly used measure to predict heat strain in workers. Different combinations of environmental conditions can create equivalent WBGT, yet it remains unknown whether biophysical, physiological, and perceptual responses vary when working in different but equivalent hot conditions. The purpose of the study was to compare body heat storage and physiological and perceptual strain during walking in hot-dry and warm-wet conditions of the same WBGT. Twelve subjects (age: 22 ± 2 y) walked for 90 min at 60% maximum heart rate in a 27.8°C WBGT environment of hot-dry (HD: 40°C, 19% relative humidity) or warm-wet (WW: 30°C, 77% relative humidity) conditions. Partitional calorimetry was used to estimate heat storage. Core temperature at 90 min (HD: 38.5 ± 0.5°C; WW: 38.4 ± 0.3°C, p = 0.244) and cumulative heat storage (HD: 115 ± 531 Kj; WW: 333 ± 269 Kj, p = 0.242) were not different. At 90 min, heart rate was not different (HD: 160 ± 19 bpm; WW: 154 ± 15 bpm, p = 0.149) but skin temperature (HD: 36.6 ± 0.9°C; WW: 34.7 ± 0.6°C, p < 0.001), thirst (HD: 6.8 a.u.; WW: 5.3 a.u. p = 0.043), and sweat rate (HD: 15.1 ± 4.4 g·min−1; WW: 10.0 ± 4.1 g·min−1, p < 0.001) were greater in HD compared to WW. Hot environments of equivalent 27.8°C WBGT created equivalent core temperature despite differences in physiological strain during exercise, including earlier onset of cardiovascular strain, greater sweat rate, and higher skin temperature compared to a WW environment. ClinicalTrials.gov ID NCT04624919. [ABSTRACT FROM AUTHOR]

The space heating in residential buildings during winters account for a considerable amount of conventional or high-grade electrical energy. Therefore, improving the performance of space heating systems with the inclusion of renewable energy sources like solar becomes crucial in order to have better occupant's comfort while reducing energy use. Phase change material (PCM) is one of the best solutions for the storage of renewable thermal energy, especially solar, which are intermittently available. PCM stores energy when surplus energy is available and deliver whenever it is required. It can be integrated with the system for energy storage as well as availing heat at a constant temperature. The present study will try to demonstrate the energy-saving by implementing the local heating with a spiral latent heat thermal energy storage system, when only a particular (local) space heating is of interest. In this work, an experimental, as well as the numerical studies of a dome over a bed were performed. Various heating coil configurations, namely floor coil, roof zig-zag, and roof spiral, were constructed to find the best configuration for the localized space heating. Experiments and simulations with the variable flow rate (0.25, 0.50, and 0.75 m/s) and varying inlet temperatures (55, 60, and 65 °C) of the heat transfer fluid were carried out. It was found that the floor coil heating gives better results as compared with the other two. It was also seen that the effect of mass flow rate and inlet temperature was not that much significant after a limit. A temperature difference of 20 °C was maintained between the space under consideration with the surrounding room. [ABSTRACT FROM AUTHOR]

• Environmental responsible new materials. • Utilization of agricultural residues for refrigeration applications. • Computational simulation of avocado seed oil as a phase change material. • Performance analysis of the avocado seed oil as a phase change material. Bio-based phase change materials (BPCMs) derived from agro-industrial residues represent an ecofriendly alternative for refrigeration applications. In this work, a BPCM was obtained by steam extraction from avocado seed and studied as a suitable cold thermal energy storage system. First, differential scanning calorimetry was used to determine that the solid-liquid phase transition occurred from -27°C to 15°C. This temperature range is of interest for the conservation different food products. The study aimed to determine the best distribution of the material, which was stored in plastic packaging bags, and placed in an insulated polystyrene thermal container. Two configurations were evaluated: (i) four bags of 75 mL, (ii) two bags of 75 mL and one of 150 mL. The temperatures of the avocado seed oil, and of the air inside the container, were measured during 6 to 8 h. It was concluded that, despite working with the same amount of avocado seed oil (300 mL) in different experiments, there was a better performance when the same volume of material was distributed in each wall. Furthermore, the utilization of avocado seed oil allowed to maintain low temperatures, suitable for food preservation during two additional hours. In the same way, in a yogurt storage experimentation of 8 h, the utilization of the avocado oil enhanced the temperature preservation by 6°C on the phase change range from 4°C to 14°C. While compared to water, the temperature difference was evaluated showing a good performance of the BPCM and an important stability on the temperature heating rate. [ABSTRACT FROM AUTHOR]

• ⋅The adsorbent is regenerated in <30 min with humid air preheated to 200 °C. • ⋅Regeneration time depends less on the dew point as humid air temperature increases. • ⋅A heat source at 200 °C is obtained even with humid air unavailable latent heat. • ⋅Maximum temperature of generated humid air theoretically estimated exceeded 220 °C. To reuse low-temperature wasted heat as a thermal resource for high temperature, a direct-contact adsorption thermal storage was focused using humid air and zeolite 13X particles as the working fluid and adsorbent, respectively. Only a few previous studies have chosen the working fluid in gaseous form because it is unavailable for latent heat in generating heat sources. Recovering waste heat in humid air to generate hotter steam is unique and becomes an originality of our present work. The time required to regenerate zeolite particles and the maximum temperature of the generated steam were investigated assuming a warm-up device for a vehicle. The time required to regenerate zeolite was investigated by changing the dew point, temperature, and superficial velocity of the inlet humid air. It was mainly affected by the temperature of the inlet air. The absorbent was regenerated within 30 min when the humid air preheated to 200 °C was supplied. On the other hand, the maximum steam temperature was investigated by changing the superficial velocity and temperature of saturated inlet humid air. As one of the significant and novel finding in this work, the steam of >200 °C was obtained as a high-temperature heat source even with saturated humid air unavailable latent heat. Moreover, as theoretical knowledge, it was revealed that the maximum temperature of the heat source can be estimated by the relationship between the heat balance on the packed bed and adsorption equilibrium. [ABSTRACT FROM AUTHOR]

• Four common latent heat functional fluids are described and compared. • Summarizes the current methods for determining the stability of PCMEs. • The mechanism and solution to the stability of PCMEs are analyzed. • The mechanism, inhibition method and research on PCME supercooling are concluded. • An overview of the latest research progress of PCMEs in various fields. As the global environment continues to deteriorate and temperatures gradually rise, it has been realized that the utilization of renewable energy is one of the most effective measures to mitigate global warming. Thermal energy storage plays a crucial role in the energy mix, and phase change materials are among the most significant and effective methods of thermal energy utilization. Phase change material emulsions, as fluid-phase phase change materials, play a significant role in thermal energy storage and heat transfer. However, issues related to stability and supercooling hinder the practical application of phase change material emulsions. Consequently, this paper explores the current research status of stability and supercooling mechanisms and technologies. Firstly, this paper provides a brief overview of the fundamental concepts of phase change material emulsions. Then, it addresses the challenges related to controlling the stability of phase change material emulsions and the issue of significant supercooling. The paper elaborates on relevant research findings in detail, mechanisms, evaluation criteria, and potential solutions. Finally, the paper outlines the research progress of phase change material emulsions in the fields of solar energy, construction, and thermal management, demonstrating their potential to advance renewable energy and various industrial sectors. [ABSTRACT FROM AUTHOR]

• Utilizing LNG by air separation, ORC, wastewater ice-making, and cold warehouse. • Two-stage freezing and pre-desalination system for desulfurization wastewater. • Optimization: exergy efficiency=70.34% output power=2.96*1011 kW LCOE=0.0623 $/kWh. • 4E analysis and improved energy efficiency=42.52% reduced CO 2 =1.234*1015kg. Against the backdrop of escalating resource depletion and the urgent quest for alternative sources, liquefied natural gas (LNG) is increasingly gaining prominence as a sustainable solution, particularly in refrigeration applications. However, its underutilization results in wasted resources. To efficiently harness the released cold energy from LNG gasification, this study proposes an integrated system comprising air separation, power generation, refrigeration, and ice thermal storage. The system undergoes optimization using the non-dominated sorting genetic algorithm II (NSGA-II) to determine the optimal operating parameters. The optimized system is comprehensively analyzed from energy, exergy, economic, and environmental perspectives. Results show that the system, with a 70t/h LNG capacity, achieves an energy efficiency of 42.52% and an exergy efficiency of 48.09%. Economically, the system incurs a cost of approximately 0.0711 $/kWh and can mitigate over 1.4504*107kg of CO 2 emissions. Compared to traditional LNG utilization systems, the integrated system demonstrates a 22.32% improvement in energy efficiency, a 7.69% enhancement in exergy efficiency, and a cost reduction of 0.0049 $/kWh. In summary, this technologically advanced and economically viable system offers a significant alternative to optimize LNG cold energy utilization. [ABSTRACT FROM AUTHOR]

This study proposes enhanced thermal stability and excellent electrochemical and photocatalytic performance of hierarchical structure of zinc-phthalocyanine (ZnPc) samples prepared through eco-friendly enhanced microwave (MW) synthesis over 5 min at T = 200 °C. The structure and morphology of the obtained ZnPc were characterized by X-ray diffraction (XRD), high-resolution transmission electron microscope (TEM), and Atomic Force Microscope (AFM). At the same time, thermal stability was analyzed using thermogravimetric analysis (TGA) and differential thermal analysis (DTA). The obtained ZnPc with high crystallinity, pure crystalline phases and reflection peaks related to the β-form of ZnPc. The average crystallite size (D) of 74 nm was determined using the Debye-Scherrer equation for a peak at 2θ = 9.30°. AFM image presented ZnPc material as a distinguished multilayered crystal with a rhombus-shaped crystal structure that seems very smooth on its surface, while TEM images showed a hierarchical structure of synthesized ZnPc self-organized assembles from the needle-like morphology which are aligned at different orientations having length up to approximately 500 nm and with 20 nm in diameter. TGA and DTA showed that the decomposition process occurred at a high temperature of 649 °C, for a heating rate of 15 °C/min, indicating good thermal stability of the investigated ZnPc. The photocatalytic activity of the hierarchically structured ZnPc was evaluated using different initial concentrations of Reactive Blue 19 (RB-19), pH value, and catalyst dose. Additionally, the electrochemical performance of ZnPc as electrode material was investigated. This study indicates facile, low-cost, and green MW method can be used for the preparation of the needle-like form of ZnPc as a promising multifunctional material for the potential applications: in thermal energy storage in future solar power technologies, as electrode material exhibiting superior voltammetric response, with cathodic and anodic current values and as photocatalyst for degradation of RB-19 and other organic dye-pollutants. [Display omitted] • Needle-like form of ZnPc were acquired through microwave-аssisted synthesis. • Thermal stability of ZnPc at high-temperature decomposition, at around 640 °C. • An electrochemical and photocatalytic properties of ZnPc were investigated. • Effects of RB-19 concentration and pH value on the decolorization rate were studied. [ABSTRACT FROM AUTHOR]

The current research work involves the design and performance assessment of a solar still, which is a conventional single‐slope basin‐type solar still (CSSBTSS) and a modified single‐slope basin‐type solar still (MSSBTSS) under the meteorological conditions of Solan city, Himachal Pradesh, India (30.90° N, 77.09° E). The individual and the combined effect of different sample quantities of sensible Himalayan Rambaan fibers (HRFs) and mass of latent paraffin wax (PW) A48 on the performance of MSSBTSS is evaluated and compared with CSSBTSS. The use of HRF material enhanced the evaporation rate significantly and improved the daytime distillates. Besides, different masses of latent PW filled inside the aluminum tubes improved the nocturnal distillates. For the analysis, three cases have been considered which are, namely: Case 1, solar still with sensible HRFs (MSSBTSS‐HRF); Case 2, solar still with latent PW A48 (MSSBTSS‐PW); and Case 3, solar still with sensible and latent material (MSSBTSS‐HRF‐PW). The results showed that the maximum thermal efficiency for Cases 1 and 2 was improved by 30.02% and 42.41% with five sample quantities of HRF material and 5000 g of PW. For Case 3, the maximum energy efficiency was 90.71% with a gain of 45.16% over CSSBTSS. The economic analysis concluded that the cost per liter of distillate yield produced using MSSBTSS‐HRF‐PW and CSSBTSS is ₹1.5 and ₹1.6, respectively. These outcomes showed the great potential of MSSBTSS‐HRF‐PW approach towards enhancing the overall performance and cost‐effectiveness of solar still. [ABSTRACT FROM AUTHOR]

This study introduces a new analytical framework that employs the image‐well method to simulate the spatial and temporal temperature distribution in vertical borehole thermal energy storage (BTES) systems. The model accommodates complex boundary shapes and conditions, including insulation, convection, and constant temperature, without requiring iterative solutions at each time step. The model's accuracy and utility are demonstrated through an application to a borehole heat exchanger cluster arranged in an octagonal shape with insulating boundaries, based on a BTES site in Drake Landing (Canada). Model predictions are validated against a finite element model, showing a root‐mean‐square error of 0.012°C. A global sensitivity analysis highlights the influence of thermal parameters on system performance, identifying the heat flux of the borehole heat exchanger as the most sensitive parameter. Overall, this approach combines the advantages of analytical and numerical techniques to provide a clear and efficient tool for evaluating BTES systems, offering significant potential for advancing sustainable energy solutions. [ABSTRACT FROM AUTHOR]

In the present study, a lab-scale for closed thermochemical heat storage reactor design is performed for seasonal thermochemical energy storage using magnesium chloride hexahydrate based on dehydration and hydration processes. Firstly, the closed reactor and plate heat exchanger are studied. Then, reactor layout modifications are examined. The dehydration process is performed under 95°C. During hydration, plates' temperature ranges from 20°C to 30°C. The impact of adding zeolite13X-4A to magnesium chloride hexahydrate is examined. The addition of zeolite13X-4A to magnesium chloride hexahydrate of 1/4 mass ratio improves the hydration process and increases its efficiency. [ABSTRACT FROM AUTHOR]

The energy consumption for cooling takes up 50% of all the consumed final energy in Europe, which still highly depends on the utilization of fossil fuels. Thus, it is required to propose and develop new technologies for cooling driven by renewable energy. Also, thermal energy storage is an emerging technology to relocate intermittent low-grade heat source, like solar thermal energy and industrial waste heat as well as to exploit off-peak electricity, for cooling applications. This review aims to summarize the recent advances in thermally driven cooling and cold storage technologies, focusing on the formation and fabrication of adopted composites materials, including sorption materials, phase change materials, and slurries. Herein, first the classifications, selection criteria, and properties for these three types of materials is discussed. Then, the application potentials of all the materials are prospected in terms of economic analysis and sustainability. [ABSTRACT FROM AUTHOR]

In this study, we will model a light-weight building made of phase change materials (PCMs) to analyze the impact of the building volume, window orientation, and air infiltration on the PCM performance. This is done by calculating the energy savings attained by the use of PCM across all of Morocco. We'll use the commercial Rubitherm panels with RT28HC as a phase change material in this work. Typically, the EnergyPlus simulation engine is chosen to perform the modeling. The impact of building volumes is also evaluated on the PCM activation for light-weight square buildings with different side lengths of 10 m, 9 m, 8 m, and 7 m. Also, we looked at how well the PCM performed in terms of energy savings and thermal regulation at different window orientation placements (south, north, west, and east) and various air infiltration rates (0.5, 1, 1.5, and 3 ACH). This paper's primary objective is to determine the energy savings for the PCM-enhanced building in Morocco, as well as the effect of building volume, window orientation, and infiltration on the PCM capabilities for stabilizing the indoor room temperature. The results show good indoor temperature stabilization during the summer, for the light-weight square building with a south-facing window and no air infiltration. This configuration was able to achieve a total fluctuation reduction of 1303.3 °C for the 10 m building in a semi-arid environment. Besides, a high energy savings percentage of 69.56% was achieved for the PCM-enhanced building with the south-oriented window and air infiltration of 0.5 air change per hour. [ABSTRACT FROM AUTHOR]

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Background: To mitigate health risks associated with occupational heat stress, workers are advised to adhere to a work‐rest regimen, and hydrate regularly. However, it remains unclear if beverage temperature influences whole‐body heat exchange during work‐rest cycles, and if responses differ in older workers who have a blunted heat loss capacity. Methods: Ten young (mean [SD]: 22 [3] years) and 10 older (60 [4] years) males performed four 15‐min bouts of moderate‐intensity cycling at a fixed rate of metabolic heat production (200 W·m−2), each interspersed by 15‐min rest in dry heat (40°C, ~12% relative humidity). On separate days, participants consumed either ice‐slurry (~0°C), standardized to provide a heat transfer capacity of 75 kJ·m−2, or an identical mass of warm fluid (37.5°C) before the first and third exercise bouts. Evaporative and dry heat exchange (direct calorimetry) and metabolic heat production (indirect calorimetry) were measured continuously to determine cumulative heat storage (summation of heat loss and heat gain) over the entire protocol. Rectal temperature was also measured continuously. Results: Relative to warm fluid, ice‐slurry ingestion reduced cumulative heat storage in young (69 [181] vs. 216 [94] kJ) and older males (90 [104] vs. 254 [140] kJ, main effect: p < 0.01), but was unaffected by age (p = 0.49). However, rectal temperature was unaffected by beverage temperature in both groups (all p ≥ 0.15). Conclusion: We show that cold fluid ingestion is an appropriate administrative control for both young and older males as it can mitigate increases in body heat content during moderate‐intensity work‐rest cycles in dry heat. [ABSTRACT FROM AUTHOR]

Refrigeration technology contributes to 10∼15% of global energy consumption, resulting in significant carbon emission. Solar-driven ejection-compression refrigeration system is promising for reducing electricity consumption and carbon emissions. However, existing solar ejection-compression refrigeration systems suffer from drawbacks of low heat utilization efficiency, oversized solar collectors, and thermal leakage due to large temperature differences of storage devices. Addressing these challenges, this study proposes and investigates a new solar-assisted ejector-compressor hybrid refrigeration system with subcooling storage coupled at intermediate temperatures. The system model is established, and the ejector model is experimentally validated. Through system modelling, an energetic and exergetic performance comparative analyses are conducted. The results indicate that the COP of the proposed system is 9.7% higher than that of traditional system combinations, producing the same cooling capacity with the same generating heat. Moreover, considering the stored cooling energy can be fully converted to cooling energy at evaporating temperatures, the COPh of the new system reaches 8.29, 24.5% higher than traditional systems. The cooling storage at 15°C with 0.325 ejector entrainment ratio suggests a reduction of approximately two-thirds in energy storage, lower temperature differences, and reduced thermal leakage, leading to decreased space and economic costs and improved energy performance. Additionally, as the COPh, COPgh, and η ex of MCS mode consistently outperform those of ZCS and HCS modes, the MCS mode is prioritized in system operation. This study underscores that the new system offers superior overall energy efficiency and requires smaller storage devices compared to traditional systems, revealing its promising practical applications. [ABSTRACT FROM AUTHOR]

Phase change composite materials (PCCMs) are a type of thermal energy storage system known for their high latent heat of fusion. In this study, PCCM samples based on peroxide-cured silicone rubber (Q) were prepared using a simple soaking procedure in molten Paraffin Wax (PW). At any fixed amount of peroxide, the rubber base samples were filled with varying amounts of graphite powder (G), 4 to 8 Wt.%, to improve the thermo-physical properties. The effect of peroxide and graphite content was then evaluated on the PW loading, PW leakage, and thermal storage performance of the resulting Q/G/PW composites. It was found that the highest ratio of the PW loading to PW leakage occurs at a peroxide content of 6 Wt.%. Moreover, the graphite particles demonstrate a significant role in PW trapping inside the rubber structure and lowering the PW leakage. Finally, the thermal studies showed that the Q/G/PW composite containing 6 wt.% of peroxide and 4 wt.% of graphite has the highest latent heat of 111.5 J/g with a PW loading of 15.2%. This sample also had the lowest thermal diffusivity and the slowest cooling and heating rate. [ABSTRACT FROM AUTHOR]

Due to their good chemical and thermal stability, high heat of melting, and suitability within the desired temperature range, organic phase change materials (PCMs) are widely used for cooling electronic devices, new energy utilization, solar thermal power generation, industrial waste heat recovery processes, and greenhouse construction. However, the flammability of organic PCMs has limited their commercial viability. In recent years, researchers have been striving to improve the flame retardancy of organic PCMs through various strategies, raising the question of which modification strategy best enhances the flame retardancy for different types of composite PCMs. Therefore, a comprehensive and timely review is needed to gain insight into the mechanism of action for flame retardant properties enhancement. This article firstly introduces the types of flame retardants and flame retardant mechanism, and briefly introduces the test methods commonly used in the laboratory for the analysis of flame retardant mechanism. Secondly, the strategies for improving the flame retardancy of organic PCMs are systematically summarized, and some scenarios for the application of organic flame‐retardant PCMs are introduced. Eventually, the challenges and future perspectives of the evolution of organic flame retardant PCMs are presented. This review is expected to provide new insights for the rational design of high flame‐retardant organic PCMs. [ABSTRACT FROM AUTHOR]

Shape-stable phase change materials (SSPCMs) are excellent for thermal energy storage applications. This study presents the first novel fluorescent switchable bio-smart SSPCMs incorporating waste. We used poly(ethylene glycol) (PEG) as the phase change material combined with leather waste (LW) and poly(glycidyl methacrylate) (PGMA). These composites achieved a relatively high shape fixity ratio (62–70%) and 100% shape recovery in both air (70 °C) and water (37 °C). They remained stable over a wide temperature range (−28.2 to 220 °C) and had high phase change enthalpies (86.8–149.7 J g−1). Composite PGL721 fully healed at 70 °C within 1.5 hours. By adding fluorescein and rhodamine B to PGL721, we created smart fluorescent SSPCMs, namely, FSSPCM1 and FSSPCM2. FSSPCM1 exhibited ON–OFF–ON fluorescence with heating, while FSSPCM2 showed ON–OFF fluorescence in the presence of Fe3+ ion (0.7 M). These smart fluorescent materials have promising applications in biomedical, textile, and soft robotic sensors and thermal storage application. [ABSTRACT FROM AUTHOR]

The document discusses the field of thermal engineering, which involves the transport and utilization of thermal energy in the design, manufacture, and use of products. It covers topics such as heat transfer mechanisms, combustion engineering, heat engines, micro- and nano-scale heat transfer, and thermal system design. The text emphasizes the importance of reducing carbon emissions, transitioning to sustainable energy systems, and addressing global climate change through technological advancements in thermal engineering. The author, Xianguo Li, provides insights into the historical development of thermal engineering and highlights the need for interdisciplinary collaboration to tackle energy challenges effectively. [Extracted from the article]

A novel room‐temperature flexible, self‐healing PCM (denoted as PEG/PHMAC) based on gel skeleton was prepared in one‐pot free‐radical polymerization by using acrylic acid (AC) and hydroxyethyl methacrylate (HM) as monomers and polyethylene glycol (PEG) as phase change component and solvent. The as‐prepared samples exhibit excellent flexibility with a bending angle of up to 120° without fracture at room temperature, playing the role of the first barrier to effectively alleviate material fracture and failure caused by stress accumulation; in addition, because of the abundant hydrogen bonds in the material, it demonstrates outstanding self‐healing ability that deep rift can be quickly repaired within 30 min after the phase change, acting as the second barrier to self‐heal the cracks of PCM generated during long‐term heat storage/release cycles. Apart from that, these materials also show extraordinary antileakage and shape‐stable property without observation of any leakage or deformation at temperature much higher than the phase change temperature. It is also proved that this gel is suitable to act as adsorption skeleton of other PEG with different molecular weight and melting point feasible for different application scenarios. With so many merits, it is expected to provide some innovative ideas for the progress of PEG‐based PCM. [ABSTRACT FROM AUTHOR]

Solid–solid phase change materials (SSPCMs) are among the most promising candidates for thermal energy storage and management. Excellent shape stability, high heat storage capacity, and satisfying mechanical properties are essential for the practical applications of SSPCMs, yet giving PCMs these characteristics at the same time remains an unmet challenge. Herein, the synthesis of PEG‐PVEG copolymers is reported with various vinyl content using a synergistic catalysis strategy, leading to novel cross‐linked PEG‐based SSPCMs via a thiol‐ene photo‐crosslinking reaction. These PCMs exhibit excellent shape stability and remarkable energy storage capabilities with latent heat up to 128.3 J g−1. The materials exhibit exceptional thermal stability and retain their energy storage capacity after 500 heating‐cooling cycles. Notably, the materials show superior mechanical strength and excellent toughness. Furthermore, the latent heat enthalpy can be further improved to 146.8 J g−1 without erosion of shape stability by the encapsulation of PEG into present SSPCM. The enhancement of both thermal and electrical conductivities is also demonstrated by the phase change composites (PCCs) incorporating multi‐walled carbon nanotubes (MWCNTs). Overall, this study presents a convenient and feasible strategy for developing SSPCMs with excellent shape stability, high latent heat and satisfying mechanical properties for thermal management. [ABSTRACT FROM AUTHOR]

Guided by the goal of improving the heat transfer efficiency of geothermal cement, the development of high thermal conductivity fillers is urgently needed. Considering the drawbacks of carbon-based fillers in deteriorating the strength and fluidity of cement, this study proposes the use of green and low-cost deep eutectic solvents (DES) loaded with graphene oxide to form nanofluids (GONF) to improve the connection between graphene oxide and cement. The thermal conductivity and basic properties of GONF-cement under thermal storage conditions (60–100 °C, 0–36%NaCl) were reported, and the influence mechanism of nanofluids was analyzed. The following interesting conclusions were found: (1) The oxygen-containing functional groups on the surface of graphene oxide were connected to active sites of DES through the formation of the hydrogen bond network, forming thermal stable nanofluids. (2) Nanofluids was proven to be a low-cost (reduce material costs of graphene oxide by 90%) and effective material for enhancing the thermal conductivity and mechanical properties of geothermal cement while maintaining appropriate fluidity and low variation of density. (3) The synergistic mechanism between nanofluids and cement is due to the fact that nanofluids promotes hydration process by providing stable reaction sites, significantly reducing the porosity and pore size of cement. The dense structure enhances compressive strength and shortens the heat transfer path. This study enriches geothermal cementing technology and provides support for the low-cost application of graphene oxide in exploration engineering. [ABSTRACT FROM AUTHOR]

Molten salts are extensively used as high-temperature heat transfer media and thermal energy storage (TES) materials in concentrating solar power (CSP) plants. Molten salt corrosion is a critical factor influencing the safe operation of the system. This work comparatively summarizes various factors influencing molten salt corrosion, including temperature, impurities, alloy composition and gas atmosphere. Additionally, the corrosion mechanisms of nitrate, carbonate, chloride, and fluoride-based mixture salts are meticulously reviewed. The demand for high-temperature storage is indeed increasing, driven by the need for more efficient and sustainable energy solutions. High-temperature storage systems, particularly those utilizing phase change materials (PCMs) and molten salts, play a key role in enhancing energy efficiency and reducing carbon footprint. By improving the efficiency of energy storage and reducing the need for fossil fuels, high-temperature storage systems help decrease greenhouse gas emissions, contributing to the fight against global warming. The paper focused on enhancing the corrosion resistance of container materials in terms of improving PCM thermal conductivity and stability. [ABSTRACT FROM AUTHOR]

The utilization of graphene aerogel encapsulated phase change materials (PCMs) presents a promising strategy to achieve solar‐thermal energy conversion and storage. However, the self‐stacking effect and inherent lattice defects in graphene aerogel significantly restrict its overall performance in the encapsulation of PCMs. Herein, interfacially self‐assembled amino‐attapulgite/graphene hybrid aerogels (GNA) are prepared via inspired by the mortise‐tenon structure. Thanks to the structural regulation of the graphene aerogel by the amino‐attapulgite nanofibers, the hybrid aerogels establish a continuous heat transfer pathway inside and ensure stable encapsulation of PCMs. The solar‐driven shape‐stabilized composite PCMs (LA/GNAb) based on GNAb impregnated with lauric acid (LA), which achieves coordinated enhancement of the effective encapsulation rate for LA (93.1%), thermal conductivity (1.164 W m−1 K−1), and photothermal conversion capability (90.5%). Drawing upon the photothermal conversion and thermal storage properties of LA/GNAb, this study demonstrates its advanced applications in solar‐driven desalination and solar‐thermoelectric generation. The evaporator and generator with integrated LA/GNAb show a high evaporation rate of 2.13 kg m−2 h−1 and a stable power density of 1.57 W m−2 under 1‐sun irradiation, respectively, which can sustain additional operating time even under the dark. This work provides new insight into the design of multifunctional solar‐driven thermal interfacial materials. [ABSTRACT FROM AUTHOR]

Solar‐powered interfacial evaporation is recognized as an emerging technology for desalination of salt‐lake water but suffers from insufficient evaporation mass under intermittent sunlight illumination. Meanwhile, salt‐lake water contains abundant noble metal ions; however, there is no effective strategy to extract them during evaporation. Hereby, an interfacial evaporator integrated with crown‐ether‐functionalized phase‐change microcapsules (Crown‐MicPCM) is designed to realize all‐weather desalination and synchronous caesium ion (Cs+) extraction of salt‐lake water. Crown‐MicPCM is constructed with an n‐docosane core for photothermal energy storage, a magnetic SiO2/Fe3O4 composite shell for easy recyclability, a polydopamine inner coat for sunlight absorption, and a crown ether outer coat for selective Cs+ adsorption. Through integrating the functions of solar energy harvest, latent heat storage, and selective Cs+ adsorption within Crown‐MicPCM, such an innovative design boosts the evaporation and adsorption performance of the developed evaporator significantly. The developed Crown‐MicPCM‐integrated evaporator exhibits a considerable improvement in freshwater production and Cs+ extraction, achieving a Cs+ adsorption capacity of 32.6 mg g−1 and an evaporation rate of 1.43 kg m−2 h−1 under one‐sun illumination. Compared with the evaporator without a phase‐change material, the Crown‐MicPCM‐integrated evaporator obtains an increase in freshwater yield by 47% and in adsorption efficiency of Cs+ by 12% under natural sunlight illumination. [ABSTRACT FROM AUTHOR]

AbstractIn thermal storage process, the aggregation, segregation, and floating of styrene–butadiene-styrene block copolymer (SBS) modifier will affect the performances of SBS-modified asphalt (SBSMA). To investigate the significant impact of macro and micro characteristics of base asphalt (BA) on the storage stability of SBSMA, we prepared SBSMA samples with three different base asphalts (BA-A, BA-B, and BA-C). Fourier transform infrared spectroscopy (FTIR), gel permeation chromatography (GPC) and atomic force microscopy (AFM) were used to investigate the microscopic properties of BAs and SBSMAs and to establish topological network nodes for their microscopic morphology. The storage performance of SBSMAs was inspected by the segregation softening point difference, complex modulus difference, and phase angle difference. Finally, the correlation analysis of microscopic structure of BA samples and storage stability of SBSMA was conducted via grey correlation methodology. The experimental results indicate that BA-A with higher molecular weight has an uneven size with honeycomb like structure, while modified asphalt using BA-A exhibits serious phase separation. In contrast, modified asphalt using BA-B and BA-C has better storage stability due to their uniform honeycomb structure size, which is consistent with the pattern presented by the microstructure of asphalt. Grey correlation analysis shows that there is a good correlation between the roughness of BA samples and the storage stability of SBSMA. In addition, the segregation softening point and the difference in complex modulus can be effective indicators for evaluating the storage stability of SBSMA. [ABSTRACT FROM AUTHOR]