HEAT AND MASS TRANSFER
·
2022
·Vol. 59
·期 5
·851-857
·
IF 2.325
Zhang Qian,Ma Fukun,Tan Wenjie,Liu Liqiang,Jing Min,Sun Tao
Inorganic hydrated salt calcium chloride hexahydrate (CaCl 2 ·6H 2 O) has a broad application prospect in the field of phase change energy storage due to its own characteristics. However, it has some problems such as large supercooling and serious phase separation, which limit its practical application. In this paper, boron nitride nanosheets (BNNSs) were applied in the CaCl 2 ·6H 2 O system. It was found that the heterogeneous nucleation of CaCl 2 ·6H 2 O can take place on the surface of BNNS. BNNS can solve the supercooling and heat transfer problems of CaCl 2 ·6H 2 O effectively. At the same time, the addition of an appropriate amount of BNNSs can improve the stability of phase change composites. Compared with pure CaCl 2 ·6H 2 O (supercooling was 22.06 °C and thermal conductivity was 0.382 W·m −1 ·K −1 ), the supercooling of CaCl 2 ·6H 2 O/1 wt% BNNS composite was only 3.89 °C and the thermal conductivity was 3.918 W·m −1 ·K −1 . CaCl 2 ·6H 2 O/0.5 wt% BNNS composite has good cycling stability. This study has scientific significance for the development and application of BNNSs in the field of phase change energy storage.
研究领域:
材料科学
·
能源存储
✓ 已验证
DOI
高影响因子
Journal of Energy Storage
·
2021
·
IF 6.583
Yixiu Xin,Hongen Nian,Jinhong Li,Jiaqing Zhao,Xiaoling Tan,Yongquan Zhou,Fayan Zhu,Hongyan Liu,Xiang Li
The efficient heat energy storage and conversion can be achieved by form-stable composite phase change material (CPCM) to cope with energy supply and demand imbalances in time and space. The modification of expanded graphite (EG) is important in promoting the phase change behavior of inorganic CPCM. The NiCo 2 O 4 with spinel structure has an excellent thermal conduction channel and great hydrophilia. In this study, the in-situ NiCo 2 O 4 was adopted to optimize the thermal conductivity and improve the thermal reliability of CaCl 2 ⋅6H 2 O (CCH)-based CPCM. It was found that the obtained CPCM exhibited the enhanced thermal conductivity (4.652 W⋅ m − 1 ⋅ K − 1 ), which was nearly 8.25 times that of CCH (0.564 W⋅ m − 1 ⋅ K − 1 ). The thermal reliability increased, which was ascribable to the improvement of hydrophilicity. Moreover, the CCH-based CPCM showed great chemical compatibility, good energy storage density (149.32 J⋅ g − 1 ), and optimized apparent activation energy (363.62 kJ⋅mol −1 ). This work will provide new insights into enhanced thermal conductivity and reliability for form-stabilized CPCM by establishing three-dimensional bimetallic oxide channels.
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
SOLAR ENERGY MATERIALS AND SOLAR CELLS
·
2019
·
IF 6.019
Ning Xie,Junyi Niu,Tong Wu,Xuenong Gao,Yutang Fang,Zhengguo Zhang
Phase change materials (PCMs) with excellent energy conservation performance have been extensively utilized in solar energy storage system . In this study, a novel kind of thermal storage composite material based on calcium chloride hexahydrate (CaCl 2 ·6H 2 O) salt hydrate as core PCM and cesium tungsten bronze (Cs x WO 3 ) nanoparticles as near-infrared (NIR) light absorbent additives is fabricated. The effect of Cs x WO 3 nanoparticles on crystalline morphology, thermal physical behaviors and light transmittance of CaCl 2 ·6H 2 O are investigated. Additionally, thermal cycle tests are conducted for stability examination. Furthermore, thermal regulating performance of double layer glass window filled with the PCM composite is tested in small chambers by being sunlight irradiated under a solar simulator . All results manifest that with the incorporation of Cs x WO 3 nanoparticles, the salt hydrate PCM composite exhibits large latent heat, low supercooling degree and high NIR light shielding ability as well as good thermal stability . When employed as the glazing window of a test room, the PCM panel has functions of reducing indoor temperature fluctuations and increasing thermal inertia. Hence, the salt hydrate/nano Cs x WO 3 PCM design in this work shows great potentials for the development of solar energy storage products in energy conservation fields.
研究领域:
材料科学
·
能量存储
·
太阳能
·
热工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Energy Storage
·
2024
·
IF 8.9
Muyang Gu,Yaoqi Huang,Kaidi Bao,Liuyi Wang,Ting Huang,Yuanyuan Li,Xiaomin Cheng
Hydrated salt phase change materials have great application value in passive thermoregulation fields due to their low phase change temperature . However, their practical applications are limited by problems such as leakage and phase separation, which require urgent attention. To solve these problems, in this study, a W/O emulsion system was constructed by sol-gel method, and microencapsulated composites with graphene oxide (GO) as the thermally conductive reinforcing phase, silica as the shell material, and calcium chloride hexahydrate (CaCl 2 ·6H 2 O, CCH) as the core material was prepared. The regular spherical SiO 2 shell layer effectively reduces the possibility of leakage of the core material. The excellent thermal conductivity of GO increases the thermal conductivity of the composites by about 41.14 % compared with that of pure CCH and maintains a latent heat of >114.1 J/g. The encapsulation of SiO 2 and the introduction of GO improve the thermal cycling stability of the composites. After 150 thermal cycles, the composites still had 96.5 % (110.1 J/g) latent heat and 99.6 % (0.708 W·m −1 ·K −1 ) thermal conductivity. The GO/SiO 2 @CCH microencapsulated composites had good temperature regulation. This study provides a promising solution for preparing hydrated salt-based shape-stabilized composites and expands their applications in construction and other fields.
研究领域:
材料科学
·
热能工程
·
能源存储
✓ 已验证
DOI
高影响因子
Journal of Energy Storage
·
2019
·
IF 3.517
Yongyichuan Zhang,Xuelai Zhang,Xiaofeng Xu,Mengyao Lu
Phase change materials can store and release large amounts of heat over a small temperature range. Phase transition interval and phase change latent heat are important indicators for phase change materials, which determine phase change materials application in different temperature zones. Due to DSC has the quality error in sampling. Therefore, the T-history method is used here to derive the phase change interval, the phase change latent heat and the thermal conductivity of phase change materials. We chose CaCl 2 •6H 2 O composite SAT, DA-MA and OA phase change materials to improve the t-history method. The formula for phase transition interval, phase change latent heat and thermal conductivity is derived. The T-history method is more accurate and can compensate for the inaccuracy of DSC. The improved T-history method is not affected by mass, and the calculated thermophysical parameters are more representative, which is suitable for the parameter calculation of phase change materials with large mass.
研究领域:
材料科学
·
热物理学
✓ 已验证
产品关联
DOI
高影响因子
AUSTRALIAN JOURNAL OF CHEMISTRY
·
2018
·Vol. 71
·期 6
·416-421
·
IF 1.059
Ouyang Dong,Zhihong Zhang,Zhenhai Fu,Xiang Li
A new phase-change material (PCM) CaCl2·6H2O + MgCl2·6H2O + NH4Cl was investigated in this paper. MgCl2·6H2O and NH4Cl were mixed with CaCl2·6H2O to obtain CaCl2·6H2O as a eutectic hydrate salt. The results show that the eutectic composition of the PCM is as follows: 90 wt- % CaCl2·6H2O, 6.25 wt- % MgCl2·6H2O and 3.75 wt- % NH4Cl; the undercooling degree is less than 1.5°C when the nucleating agent is 2 wt- % SrCl2·6H2O or 1.5 wt- % Ba(OH)2·8H2O. The phase-change temperature and latent heat are respectively 25.3°C and 144.3 J g−1 when the composition is 90 wt- % CaCl2·6H2O, 6.25 wt- % MgCl2·6H2O, 3.75 wt- %, NH4Cl, with 2 wt- % SrCl2·6H2O as nucleating agent, and 2 wt- % carboxymethyl cellulose as thickener. In addition, when the composition is changed to 90 wt- % CaCl2·6H2O, 6.25 wt- % MgCl2·6H2O, 3.75 wt- % NH4Cl, 1.5 wt- % Ba(OH)2·8H2O and 2 wt- % carboxymethyl cellulose, the phase change temperature and latent heat are 25.2°C and 139.3 J g−1, respectively.
研究领域:
材料科学
·
热能存储
·
化学工程
✓ 已验证
DOI
高影响因子
ENERGY
·
2022
·
IF 8.857
Yan Wang,Jiahao Sui,Zijie Xu
As a cost-effective phase change thermal storage material, calcium chloride hexahydrate exhibits high heat capacity and holds tremendous promise in building energy savings . However, as a kind of hydrated salt , it also suffers from the issues of phase stratification and high degree of supercooling. Thus, present work has studied the inorganic mixtures of hydrated chloride salts and prepared a novel kind of binary eutectic phase change thermal storage material via replacing calcium chloride hexahydrate by various mass ration of magnesium chloride hexahydrate. The initial research results showed that both the components liquefied simultaneously during melting and the phase stratification of eutectic system could be effectively alleviated. Nucleating agent led to a good restrain to the supercooling of inorganic eutectic and the subcooling degree could be found as small as 1 °C.Meanwhile, the small amount of additive would little affect the melting point and enthalpy of fusion of energy storage material. The thermal cycling tests showed that our as-prepared eutectic salts exhibited good thermal reliability with fixed phase transition temperature and almost no diminution of enthalpy, which indicated that this novel binary eutectic material possessed excellent and stable performance suitable for heat storage in building energy savings.
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
SOLAR ENERGY MATERIALS AND SOLAR CELLS
·
2014
·
IF 5.03
Gang Li,Binbin Zhang,Xiang Li,Yuan Zhou,Qingguo Sun,Qiang Yun
The preparation, characterization and modification of eutectic hydrate salt (CaCl 2 ·6H 2 O–MgCl 2 ·6H 2 O) as a new phase change material (PCM) were investigated in this paper. CaCl 2 ·6H 2 O was prepared using industrial grade calcium chloride (CaCl 2 ), and then 10, 15, 20 and 25 wt% MgCl 2 ·6H 2 O was added into CaCl 2 ·6H 2 O respectively in order to obtain CaCl 2 ·6H 2 O–MgCl 2 ·6H 2 O eutectic hydrate salt PCM. The modification of CaCl 2 ·6H 2 O-25 wt% MgCl 2 ·6H 2 O material was designed by a uniform experimental method to select the efficient nucleating and thickening agents. The results show that SrCl 2 ·6H 2 O and SrCO 3 can be effective nucleating agents , and hydroxyethyl cellulose (HEC) is an excellent thickener. For CaCl 2 ·6H 2 O-25 wt% MgCl 2 ·6H 2 O material with 3 wt% SrCl 2 ·6H 2 O, 1 wt% SrCO 3 and 0.5 wt% HEC, the supercooling is reduced to 2 °C, and its phase change temperature and latent heat are 21.4 °C and 102.3 J/g, respectively.
研究领域:
材料科学
·
储能技术
·
热能工程
✓ 已验证
DOI
高影响因子
APPLIED THERMAL ENGINEERING
·
2020
·
IF 4.725
Tao Wang,Xishan Zhou,Zhao Liu,Jiawei Wang,Yongsheng Zhang,Wei-Ping Pan
As an inorganic phase change material (PCM), CaCl 2 ·6H 2 O is an effective energy storage material because its energy can be transformed around 30 °C through the melting and crystallization. The different compositions of PCM were prepared in order to decrease the phase transition temperature to 20–25 °C and to improve its capability of heat storage and release. MgCl 2 ·6H 2 O was added as a nucleating agent and the composite PCMs (CPCMs) of CaCl 2 ·6H 2 O/MgCl 2 ·6H 2 O binary salt system was prepared. At the same time, SrCl 2 ·6H 2 O was added to reduce the supercooling degree of inorganic PCM. As a thickener, hydroxyethyl cellulose (HEC) was also included to improve the recycling ability. With the application of thermogravimetric analysis and differential scanning calorimeter, the phase transition temperature, thermal properties of CPCMs, supercooling degree and thermal cycle performance were studied by changing the content of each component in the CPCMs. The results demonstrated that the phase transition temperature of PCM with 35% MgCl 2 ·6H 2 O, 5% SrCl 2 ·6H 2 O, 0.5% HEC balanced by CaCl 2 ·6H 2 O was reached to 23 °C. The phase change latent heat of PCM was kept at 130 J/g. The degree of supercooling was kept within 0.7 °C and the recyclability was greatly improved after 100 cycles.
研究领域:
材料科学
·
热能存储
·
相变材料
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Lina Chen,Xuelong Chen,Baozheng Cui,Jingbo Zhu,Ningjing Bai,Wei Wang,Huixin Wang,Zewen Li,Haijun Niu,Zhe Wang
In recent years, solar energy interfacial evaporation technology has been extensively explored for seawater desalination and wastewater treatment. However, salt accumulation and complex fabrication of evaporator largely constrains the applications of this technology in practice. Here, one type of interpenetrating polymer network hydrogel composing of agarose (AG) and polyvinylpyrrolidone (PVP) using polypyrrole (PPy) as the light absorbent was fabricated via “hot-ice” template method, which was featured with pitted-surface and microchannels structure. The evenly arranged pits on the surface of the hydrogel can absorb the sunlight as much as possible and convert it into heat energy, improving the efficiency of photothermal absorption. The water channels generated by the formation of CaCl 2 ·6H 2 O crystals can transport water from the bottom to the evaporation interface elevating the transmission rate and accelerating the exchange of gradient salt concentration. As consequences, excellent salt resistance of the hydrogel can be obtained, achieving seawater evaporation rate as high as 3.2 kg m −2 h −1 . In addition, the outstanding ion rejection performance, strong acid/alkali purification capability, and good treatment capacity for heavy metal ions and dye wastewater were also demonstrated.
研究领域:
环境科学
·
材料科学
·
化学工程
·
水处理
✓ 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）