MACROMOLECULES
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2025
·
IF 5.2
Yuan Yuan,Yu Jiang,Zhihao Huang,Zhiguang Xu,Tao Zhang,Yan Zhao
Phase change material (PCM)-microencapsulated monolithic composites hold considerable promise in applications for latent heat storage and release, but they face the issue that the microencapsulated PCMs, when in the liquid state, might leak via an open pathway. Herein, we report the synthesis of solid–solid phase change composites from thermoreversible octadecane (OD) gel-in-water emulsions through in situ closed-cell polyHIPE generation and encapsulation. The thermoreversible OD gels, formed simply by heating OD and a low-molecular-weight gelator together, exhibit a reversible crystal-gel phase transition and a gel–liquid phase transition. Through light-driven interface-initiated radical polymerization, solid–solid phase change composites have been fabricated from Pickering emulsions containing the thermoreversible OD gel as the dispersed phase via in situ closed-cell polyHIPE generation and encapsulation. The resulting composites show predesignable external shapes, negligible leakage even for fractured samples after 10 heating–cooling cycles, high flexibility, and robust compression. The composites possess extremely high heats of melting and crystallization (up to 197.5 J/g) and good reusability. The advantageous properties enable the solid–solid composites to be excellent candidates for efficient latent heat storage and temperature management.
研究领域:
材料科学
·
能源工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Energy Storage
·
2024
·
IF 8.9
Zijie Geng,Chen Shi,Qing Zhao,Liu Yang
A new phase change heat storage coating is prepared in this study, which can regulate indoor temperature. The composite phase change material (D/PCM) with modified diatomite and paraffin was prepared by the porous material adsorption method. D/PCM and coatings were characterized by differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and cycle leakage ratio. The SEM results showed that diatomite modified by high-temperature expansion and acidification has a better adsorption capacity . D/PCM and C-D/PCM (heat storage coatings with D/PCM) have nearly no leakage and still show good thermal stability after 500 thermal cycles. In addition, the heat transfer process in a physical model of a reinforced concrete wall was simulated based on hourly variations in summer temperatures in Xi'an, China. The results show that C-D/PCM with a phase change temperature of 26–28 °C and a thickness of 5 mm provides greater heat storage capacity, good temperature regulation and energy savings within a reasonable thickness range in summer. The selected PCM coatings have a small temperature fluctuation (2.54 °C) and a high phase change utilization ratio (75 %), which can reduce the wall cooling load by 18.67 % in summer and save energy.
研究领域:
材料科学
·
建筑节能
✓ 已验证
DOI
高影响因子
Journal of Thermal Science
·
2021
·Vol. 30
·期 6
·2002-2014
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IF 2.438
Shao Xuefeng,Yang Sheng,Chen Chenlin,Fan Liwu,Yu Zitao
The temperature-dependent rheological behaviors of five selected binary eutectic mixture sugar alcohols, with great potential for latent heat storage in the range of 353.15 K to 523.15 K, were investigated. It was found that the rheological behaviors of the mixture sugar alcohols depend on those of the pure compounds as well as their molar ratios. The two mixtures of xylitol (75 mol%)+erythritol and erythritol (84 mol%)+d-mannitol behave like pseudoplastic fluids with typical non-Newtonian shear-thinning behaviors, as indicated by the power law index of 0.99 (<1). The mixture of d-mannitol (70 mol%)+d-dulcitol is a nonlinear Bingham fluid, exhibiting a slight yield stress (0.001 Pa to 0.01 Pa) at low shear rates. The rest two mixtures containing the cyclic-structured inositol behave like Herschel-Bulkley fluids. The infinite shear viscosities of the eutectic mixtures over the entire temperature range appear to be higher than those of their respective pure compounds, except for inositol. The mixture of xylitol (75 mol%)+erythritol at its melting point shows higher dynamic viscosity of about 0.546 Pa·s than the values of about 0.396 Pa·s and 0.035 Pa·s for xylitol and erythritol, respectively. In addition, the activation energies of viscous flow of the mixtures, as determined by fitting the dynamic viscosity-temperature curves using the Arrhenius model, also exhibit higher values than those of their pure compounds. The activation energy of viscous flow of the mixture xylitol (75 mol%)+erythritol was determined to be about 92 400 J/mol in the supercooled liquid state, while the supercooled liquid xylitol and erythritol have much lower values of 83 500 J/mol and 51 900 J/mol, respectively. Both the increased dynamic viscosities and activation energies of viscous flow can result in deteriorated crystallization performance during latent heat retrieval.
研究领域:
材料科学
·
热能工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Energy Storage
·
2023
·
IF 9.4
Xue-Feng Shao,Sheng Yang,Hong-Yi Shi,Li-Wu Fan,Yan-Ping Yuan
Sugar alcohols have been proposed as a class of potential phase change materials (PCMs) for medium-temperature latent heat storage . The present work investigated the cycling stability of four pure and three mixture sugar alcohols by a specially-designed test setup, followed by a comprehensive evaluation based on their phase change behaviors (reported in our previous publication) and stability. It was found that the latent heats of fusion/crystallization degrade upon consecutive melting-crystallization cycles, and a higher degree of superheat Δ T sh leads to a faster degradation. An extremely low level of only 10.5 % degradation was obtained for erythritol after 200 cycles at a relatively low Δ T sh of 20 °C. The corresponding degrees of supercooling Δ T sc become higher due to the remarkable reduction of crystallization temperatures . It was shown that introducing protective nitrogen gas could suppress oxidation and improve cycling stability. The cycles of half degradation on latent heat of fusion was ~3.6 times with nitrogen protection. A comprehensive evaluation identified that the crystallization-related issues and poor stability are the primary challenges for sugar alcohols. Nevertheless, other than common PCMs, some particular application scenarios like controllable latent heat retrieval and seasonal heat storage can be hopefully developed by virtue of the deep supercooling nature of sugar alcohols.
研究领域:
材料科学
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能源存储
✓ 已验证
产品关联
DOI
高影响因子
Advances in Materials Science and Engineering
·
2022
·Vol. 2022
·期 1
·3109178
·
IF 2.098
Yuxian Wang,Jing Gu,Xian Li,Yan Zhu,Hongyun Hu,Huan Liu,Guangqian Luo,Hong Yao
Cellulose-originated three-dimensional graphene oxide CNT-modified LiOH·H 2 O (3D-GO-CNTs-LiOH·H 2 O) was synthesized by the hydrothermal method. LiOH·H 2 O nanoparticles (5–50 nm) were homogeneously dispersed inside the 3D-GO-CNTs frames. The composite showed enhanced heat storage density, excellent thermal conductivity, and greatly improved hydration rate due to both the hydrophilic reaction interface of 3D-GO-CNTs frames and reduced size of LiOH·H 2 O nanoparticles. LiOH·H 2 O content ratio of 23% (3D-GO-CNTs-LiOH·H 2 O-1) results in best heat storage performance with activation energy of 23.8 kJ/mol, thermal conductivity of 3.06 W/m·K, and heat storage capacity of 2800 kJ/kg. 3D-GO-CNTs-LiOH·H 2 O shows 4.2 folders heat storage capacity than that of pristine LiOH·H 2 O after the same hydration reaction. Other composite materials also show good performance: 3D-GO-CNTs-LiOH·H 2 O-2 (activation energy: 28.5 kJ/mol, thermal conductivity: 2.33 W/m·K, and heat storage capacity: 2051 kJ/kg.); 3D-GO-CNTs-LiOH·H 2 O-3 (activation energy: 32.3 kJ/mol, thermal conductivity: 2.01 W/m·K, and heat storage capacity: 1983 kJ/kg.). The addition of cellulose originated 3D-GO-CNTs was proved to be an excellent strategy to boost the heat storage performance of LiOH·H 2 O.
研究领域:
材料科学
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化学工程
·
能源存储
✓ 已验证
DOI
高影响因子
BIOMACROMOLECULES
·
2022
·
IF 6.978
Wenbin Shi,Nijia Song,Yanping Huang,Chao He,Man Zhang,Weifeng Zhao,Changsheng Zhao
Burn injury has become a crucial public health issue worldwide. It is necessary to explore new methods to reduce heat damage and improve healing efficiency during burn injury treatment. In this study, a kind of hydrogel combining heat storage capacity and thermal conductivity was fabricated via a one-pot method for burn therapy. The novel hydrogel was easily prepared by in situ cross-linking polymerization, using poly(ethylene glycol) (PEG) derivatives, oligo(ethylene glycol) methacrylate and 2-(2-methoxyethoxy) ethyl methacrylate, as thermally responsive base materials and hydroxylated multiwall carbon nanotubes (CNT-OH) as thermally conductive fillers. By dispersing CNT-OH, a thermally conductive network was formed in the hydrogel, leading to an increase in the thermal conductivity. The cooling performance, thermal conductivity, heat storage property, swelling performance, rheological and mechanical properties, biocompatibility, in vivo cooling effect, and wound healing properties of the prepared hydrogel were systematically investigated. The hydrogel consisted of thermally responsive PEG derivatives, and CNT-OH performed a function of rapid heat absorption, further reduced thermal damage, and promoted wound healing. The improved cooling performance of the hydrogel was ascribed to the improved thermal conductivity, enhanced heat storage capacity, and good adhesive ability. Thus, the hydrogel has great potential to be practically applied in burn therapy, laser treatment, cooling fabrics, heat-protective clothing, and other emergency scenarios.
研究领域:
生物材料学
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医学工程
·
创伤修复
✓ 已验证
DOI
高影响因子
CARBOHYDRATE POLYMERS
·
2018
·
IF 5.158
Xiaonan Huo,Wei Li,Yu Wang,Na Han,Jianping Wang,Ning Wang,Xingxiang Zhang
In order to reduce environmental pollution during microencapsulating phase change materials and expand their applications as well, a novel eco-friendly microencapsulated/nanoencapsulated phase change materials (Micro/NanoPCMs) and the corresponding encapsulation method were proposed and discussed in this study, where the natural chitosan and side-chain crystallizable comb-like polymer were selected as shell material and core material, respectively. During the encapsulating process via coacervation, the effects of different core-shell ratios on the morphology and thermal storage properties of microcapsules were discussed. FE-SEM and TEM was employed to investigate the morphology and microstructure of the microcapsules. The thermodynamics performance of microcapsules was studied using TGA and DSC. The encapsulation efficiency of microcapsules ranged from 49.82% to 68.99%, and the thermal stability temperature of microcapsules was measured to be 243.2 °C. The fabrication process where natural raw materials were employed and showing promising applications in such fields as medical treatment.
研究领域:
材料科学
·
环境科学
·
生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SOLAR ENERGY MATERIALS AND SOLAR CELLS
·
2022
·
IF 7.305
Nan Sheng,Yunfei Ge,Yunqi Guo,Chunyu Zhu,Zhonghao Rao
This study reports the successful fabrication of Cu@Al 2 O 3 macro-encapsulated metallic PCMs for high-temperature thermal storage over 1000 °C. Cu powders are employed as raw material which are spherulitized to core balls in millimeter-size, and subsequently the core balls are cladded with Al 2 O 3 ceramic shells. After the low-temperature pre-sintering and subsequent high-temperature sintering treatment, the Cu@Al 2 O 3 macrocapsules which contain gaps between the shells and cores are successfully prepared. The core balls are consisted of Cu powders which are not densified but are porous, offering buffer spaces to accommodate the thermal volume expansion during high-temperature sintering and melting of Cu. As a comparison, Cu@Al 2 O 3 macrocapsules prepared by directly coating the commercial solid Cu balls are leaky. Thermal analysis indicates that the metallic core PCM has a melting temperature of 1063 °C and a latent heat of around 210 J/g. The macrocapsules are also highly durable as confirmed by the melting-solidification cycling test. These results demonstrate that the Cu@Al 2 O 3 macrocapsules are applicable as high-temperature heat storage media, which can find useable applications in advanced high-temperature thermal energy storage systems .
研究领域:
材料科学
·
能源工程
✓ 已验证
产品关联
DOI
高影响因子
ACS Omega
·
2022
·
IF 4.132
Yu Jiang,Qian Wang,Sisi Tian,Zhenhua Luo,Dong Wang,Yun Bai,Wu Lu,Tong Zhao
A novel NaF phase change microcapsule with a carbon shell (NaF@C microcapsule) was prepared by a simple approach. The carbon shell was synthesized by carbonization of a resole-type phenolic resin shell, which was encapsulated onto the surface of NaF particles by a simple phase separation process induced by tetraethoxysilane. Scanning electron microscopy, transmission electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, differential scanning calorimetry (DSC), and thermogravimetric analysis were used to characterize the morphology, composition, crystal phase, and thermal properties of the microcapsules. The size of the NaF@C microcapsule was 3–5 μm with a core–shell structure. DSC results showed that the melting point of the prepared NaF@C microcapsule was 988 °C, and the enthalpy value was 192 J/g. The prepared NaF@C microcapsules retained the powder morphology after 30 times of heat treatment at 1100 °C, with no NaF leakage detected, and the micromorphology remained stable, presenting good thermal stability. The NaF@C microcapsules can be used in the fields of thermal protection and thermal management in extreme high-temperature environments such as aerospace and solar energy.
研究领域:
材料科学
·
能源工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CARBON
·
2022
·
IF 11.307
Jinlong Li,Qing Chang,Chaorui Xue,Jinlong Yang,Shengliang Hu
Polymer phase change materials (PCMs) often suffer from the attenuation of thermal storage capacities and the shrinkage of storage duration after adding conventional high heat conduction matters, resulting in low efficiency of heat storage and utilization. Here we report a novel strategy in which carbon dots (CDs) evenly distributed into polyethylene glycol (PEG) act as local self-heating agents to shorten thermal transfer distances. As a result, CDs enhance the phase change enthalpies of PEG-related PCMs by their interface interaction, resulting in 13.7% higher than the theoretical value. Moreover, the hybrids of CDs and PEG are impregnated into the melamine sponge modified with CDs and polydimethylsiloxane through vacuum induced infiltration technique to prevent the liquid leakage . The obtained composite shows the long heat storage duration and achieves 82.57% of solar-to-thermal storage efficiency as well as 92.27% of the heat release efficiency. In particular, its outstanding hydrophobicity and stability in shape and heating–cooling cycles allows it to practically apply in solar-thermal energy conversion and storage.
研究领域:
材料科学
·
能源科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Energy Storage
·
2024
·
IF 8.9
Ruizhi Zheng,Renjie Chen,Delong Xie,Xinjie Luo,Yu Wang,Yang Bai,Sihao Yin,Jian Xiang,Hongfei Zhang,Yi Mei
Phosphorus-modified hexadecanol is regarded as a promising heat storage medium for form-stable phase-change materials (FSPCMs) because of its high energy storage density and good thermal stability . In this study, a novel FSPCM was fabricated using phosphorus-modified hexadecanol, 1-oxo-4-hydroxymethyl-2,6,7-trioxa-l-phosphabicyclo [2.2.2] octane (PEPA), and pentaerythritol (PER). Among all the samples, FSPCM (P3), containing 9 % PEPA and 3 % PER, exhibited the optimal thermal storage performance and flame-retardant properties. Its latent heat was 122.5 J/g, and its photo-to-heat conversion efficiency was 61.8 %. The limiting oxygen index of P3 approached 29.5 %, and the UL-94 V -0 rating was attained. The decomposition and fire-retardant mechanism were inferred based on the analysis of char residues and the gaseous phase to determine the interaction between the PCMs and flame retardants.
研究领域:
材料科学
·
能源科学
✓ 已验证
产品关联
DOI
高影响因子
Sustainable Cities and Society
·
2018
·
IF 3.073
Xiaoling Cao,Yanping Yuan,Bo Xiang,Fariborz Haghighat
In order to improve melting rate of latent heat storage system, the effect of natural convection during melting process in eccentric horizontal shell and tube storage unit is investigated in this study. The melting performance in different eccentricity ( e ) and boundary temperature ( T w ) is obtained through experiment research and numerical simulation. During the experiment study, the temperature variations at different positions are measured. Then, the temperature and fluid field, movement of the phase interface are analyzed by numerical simulation. With the increase of eccentric distance, the natural convection dominated area increases, so the melting rate is improved. The eccentric geometry with e = 30 mm and T w = 80 °C results in a 57% decrease in the total melting time. The special attention is paid on the evolution of natural convection and the heat transfer mechanism during the melting process, so the parameter of time-average heat transfer coefficient ( h ¯ ) is proposed. h ¯ is relatively higher in an eccentric geometry which illustrate the heat transfer efficiency is improved. The variation of h ¯ also reflects transformation of the heat transfer characteristic in concentric unit and eccentric unit.
研究领域:
工程热物理
·
能源存储技术
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）