APPLIED ENERGY
·
2024
·
IF 10.1
Kai Liu,Ling Wang,Zhifeng He,Pengcheng Lin,Ying Chen
Phase change cold storage , as an emerging cold chain method of maintaining a low-temperature environment and effectively ensuring the quality of biochemical reagents, is extensively utilized because of its benefits of high energy density , low cost, energy conservation and environmentally friendly mode. However, the low thermal conductivity of working medium affects its cold charging/discharging rate and operating efficiency. Meanwhile, the high leakage characteristic in the phase change process leads to a decrease of cold storage capacity and contamination of items. This work proposes the efficient utilization of cold energy enabled by leakage-free phase change cold storage brine gels with extraordinary high thermal conductivity towards biochemical reagent cold chain. Phase change thermal storage gel is prepared by confining brine in the sodium polyacrylate‑calcium alginate network and porous adsorption of expanded graphite . The prepared materials present leak free characteristics and almost 100% mass retention rate. Expanded graphite addition enables the thermal conductivity increase from 0.542 W m −1 K −1 to an extremely high value of 2.766 W m −1 K −1 (an increase of 510%). The enthalpy value of the cold storage brine gel is as high as 144 Jg −1 , stably releasing cold at around −24 °C. By regulating the distribution of cold storage working medium, the minimum temperature difference inside the apparatus can be reduced from 6.7 °C to about 1 °C. Finally, performance-enhancing phase change cold storage materials and apparatus in the cold chain of biological reagents is fruitful, effectively providing a long-lasting and uniform low-temperature environment.
研究领域:
材料科学
·
生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Energy Materials
·
2021
·
IF 6.024
Li-Mei Peng,Zhao Xu,Wei-Yu Wang,Xing Zhao,Rui-Ying Bao,Lu Bai,Kai Ke,Zheng-Ying Liu,Ming-Bo Yang,Wei Yang
Solid–liquid phase change materials (PCMs) are widely used in heat management. However, the requirement of no leakage of solid–liquid PCMs during phase transition and suitable deformability at evaluated temperature are contradictory when PCMs are used as thermal interface materials (TIMs). Vitrimer, a kind of material that combines with the advantages of both thermoplastics and thermosets, may be a solution. Herein, polyethylene wax vitrimer (PEWV) is prepared through the dioxaborolane exchange reaction for TIMs with leakage-proof and high-energy-storage ability. Microphase separation occurs between highly cross-linked skeleton and slightly cross-linked chains, which solves the leakage problem of polyethylene wax. Simultaneously, PEWV can achieve a high latent heat storage capacity of about 121.0 J g–1, about 74% of that of PEW, owing to the negligible effect of dynamic cross-linking on the crystallization of PEW. Meanwhile, PEWV can be plastically deformed and tightly adhered to the rigid surface under a slight external force at the phase change temperature, filling the gap at macro- and microscales for improving the heat transfer efficiency. The composites of PEWV and thermal conductive filler show more excellent performance as TIMs than commercial thermal conductive pads. PEWV with no leakage, excellent plasticity, and high latent heat storage capacity provides great application potential in heat storage and thermal interface management.
研究领域:
材料科学
·
热管理技术
✓ 已验证
DOI
高影响因子
Frontiers of Materials Science
·
2022
·Vol. 16
·期 4
·1-13
·
IF 2.612
Chen Fenglan,Liu Xin,Wang Zhengya,Tie Shengnian,Wang Chang-An
As a kind of essential hydrated salt phase change energy storage materials, mirabilite with high energy storage density and mild phase-transition temperature has excellent application potential in the problems of solar time and space mismatch. However, there are some disadvantages such as supercooling, substantial phase stratification and leakage problem, limiting its further applications. In this work, for the preparation of shaped mirabilite phase change materials (MPCMs), graphene (GO), sodium carboxymethyl cellulose (CMC), and carbon nanofibers (CNFs) were used as starting materials to prepare lightweight CMC/rGO/CNFs carbon aerogel (CGCA) as support with stable shape, high specific surface area, and well-arranged hierarchically porous structure. The results show that CGCA has regular layered plentiful pores and stable foam structure, and the pore and sheet interspersed structure in CGCA stabilizes PCMs via capillary force and surface tension. The hydrophilic aerogels supported MPCMs decrease mirabilite leaking and reduce supercooling to around 0.7–1 °C. The latent heats of melting and crystallization of CGCA-supported mirabilite phase change materials (CGCA-PCMs) are 157.1 and 114.8 J·g −1 , respectively. Furthermore, after 1500 solid—liquid cycles, there is no leakage, and the retention rate of crystallization latent heat is 45.32%, exhibiting remarkable thermal cycling stability.
研究领域:
材料科学
·
能源工程
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Xueming Yang,Chunbo Li,YongFu Ma,He Chi,Zongjie Hu,Jianfei Xie
Phase change materials (PCMs) are widely used in the field of thermal management and energy storage, but both low thermal conductivity and leakage problem limit their broad applications. In this work, a 3D porous graphite (PG) foam was prepared by a pressing and drying method with solid mixture of graphite powder and ammonium bicarbonate (NH 4 HCO 3 ), and it was used as the thermal conductive skeleton and shape stabilizer of PCMs. PG/paraffin composite PCMs (CPCMs) were then prepared by the vacuum impregnation of liquid paraffin into PG foam. It showed that the skeleton of 3D PG foam greatly improves the thermal conductivity of CPCMs. The prepared PG/paraffin CPCMs exhibited an ultra-high thermal conductivity of 19.27 Wm -1 K −1 at a volume fraction 35.55% of graphite, which is about 76.08 times higher than that of paraffin. The heat conduction mechanism of the PG/paraffin CPCMs are analyzed, and it is found that Maxwell-Eucken model can be used to accurately predict its thermal conductivity. Moreover, the CPCMs show good performance of thermal shape stability and exhibit superior anti-leakage characteristic. The proposed method for the preparation of 3D PG foam is robust, and the excellent performance of their based CPCMs will be promising in the field of heat dissipation and thermal storage.
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
危险品化学品经营许可证（带存储）