scholarly journals The Effect of Hydroxylated Multi-Walled Carbon Nanotubes on the Properties of Peg-Cacl2 Form-Stable Phase Change Materials

Energies ◽  
2021 ◽  
Vol 14 (5) ◽  
pp. 1403
Author(s):  
Lingyu Zheng ◽  
Xuelai Zhang ◽  
Weisan Hua ◽  
Xinfeng Wu ◽  
Fa Mao
Keyword(s):  
Thermal Conductivity ◽  
Carbon Nanotubes ◽  
Phase Change ◽  
Phase Change Material ◽  
Phase Change Materials ◽  
Interfacial Thermal Resistance ◽  
Stable Phase ◽  
Multi Walled Carbon Nanotubes ◽  
Walled Carbon Nanotubes ◽  
Change Material

Calcium ions can react with polyethylene glycol (PEG) to form a form-stable phase change material, but the low thermal conductivity hinders its practical application. In this paper, hydroxylated multi-walled carbon nanotubes (MWCNTs) with different mass are introduced into PEG1500·CaCl2 form-stable phase change material to prepare a new type of energy storage material. Carbon nanotubes increased the mean free path (MFP) of phonons and effectively reduced the interfacial thermal resistance between pure PEG and PEG1500·CaCl2 3D skeleton structure. Thermal conductivity was significant improved after increasing MWCNTs mass, while the latent heat decreases. At 1.5 wt%, composite material shows the highest phase change temperature of 42 °C, and its thermal conductivity is 291.30% higher than pure PEG1500·CaCl2. This article can provide some suggestions for the preparation and application of high thermal conductivity form-stable phase change materials.

Improving thermal conductivity and decreasing supercooling of paraffin phase change materials by n-octadecylamine-functionalized multi-walled carbon nanotubes

RSC Advances ◽  
2014 ◽  
Vol 4 (69) ◽  
pp. 36584-36590 ◽  
Author(s):  
Qianqiu Tang ◽  
Jun Sun ◽  
Shuangmin Yu ◽  
Gengchao Wang
Keyword(s):  
Thermal Conductivity ◽  
Carbon Nanotubes ◽  
Phase Change ◽  
Phase Change Materials ◽  
Multi Walled Carbon Nanotubes ◽  
Walled Carbon Nanotubes

N-Octadecylamine-functionalized multi-walled carbon nanotubes (f-MWCNTs) are introduced to paraffin to improve the thermal conductivity and decrease supercooling of phase change materials.

scholarly journals Silver microsphere doping porous-carbon inspired shape-stable phase change material with excellent thermal properties: preparation, optimization, and mechanism

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Junwei Zhang ◽  
Yan Chen ◽  
Zeguang Nie ◽  
Zhengshou Chen ◽  
Junkai Gao
Keyword(s):  
Thermal Conductivity ◽  
Phase Change ◽  
Phase Change Material ◽  
Porous Carbon ◽  
Phase Change Materials ◽  
Agricultural Waste ◽  
Raw Material ◽  
Stable Phase ◽  
Cotton Stalk ◽  
Change Material

AbstractIn this study, silver microspheres (SMS) were introduced into cotton stalk porous-carbon (CSP) to prepare silver microsphere doping porous-carbon (SMS-CSP), and then SMS-CSP was used as the matrix of polyethylene glycol (PEG) to synthesize shape-stable phase change material of PEG/SMS-CSP. It was found that the introduction of SMS into CSP could not only greatly improve the loading capacity of the porous-carbon for PEG, but also could increase the thermal conductivity of PEG/SMS-CSP. Additionally, the method of introducing SMS into porous-carbon had the advantages of environmental protection and simple operation. Moreover, the raw material of cotton stalk is a kind of agricultural waste, which has the merits of wide source, low price and easy to obtain. Furthermore, in the preparation of cotton stalk porous-carbon, with the increase of pyrolysis temperature the thermal conductivity of PEG/SMS-CSP could be enhanced significantly. The mechanism about the enhancement of thermal conductivity was clarified, which could provide more basic theory for the study about the thermal conductivity of shape-stable phase change materials (ss-PCMs) based on porous-carbon.

Effects of carbon nanotubes additive on thermal conductivity and thermal energy storage properties of a novel composite phase change material

2018 ◽  
Vol 53 (21) ◽  
pp. 2967-2980 ◽  
Author(s):  
Ahmet Sarı ◽  
Alper Biçer ◽  
Gökhan Hekimoğlu
Keyword(s):  
Thermal Conductivity ◽  
Carbon Nanotubes ◽  
Differential Scanning Calorimetry ◽  
Phase Change ◽  
Phase Change Material ◽  
Phase Change Materials ◽  
Scanning Calorimetry ◽  
Composite Phase Change Materials ◽  
Composite Phase Change Material ◽  
Change Material

Fatty acids are commonly preferred as phase change materials for passive solar thermoregulation due to their several advantageous latent heat thermal energy storage (LHTES) properties. However, further storage container requirement of fatty acids against leakage problem during heating period and also low thermal conductivity significantly limit their application fields. To overcome these drawbacks of capric acid–stearic acid eutectic mixture as phase change material, it was first impregnated with expanded vermiculite clay by melting/blending method and then doped with carbon nanotubes. The effects of carbon nanotubes additive on the chemical/morphological structures and LHTES properties of the composite phase change material and thermal enhanced change phase change materials were investigated by scanning electron microscope, Fourier transform infrared spectroscopy, X-ray diffraction, differential scanning calorimetry and thermogravimetric analysis analysis techniques. The differential scanning calorimetry results showed that the form-stable composite phase change materials and thermal enhanced composite phase change materials have melting temperatures in the range of 24.35–24.64℃ and latent heat capacities between 76.32 and 73.13 J/g. Thermal conductivity of the composite phase change materials was increased as 83.3, 125.0 and 258.3% by carbon nanotubes doping 1, 3 and 5 wt%. The heat charging and discharging times of the thermal enhanced -composite phase change materials were reduced appreciably due to the enhanced thermal conductivity without notably influencing their LHTES properties. Furthermore, the thermal cycling test and thermogravimetric analysis findings proved that all fabricated composites had admirable thermal durability, cycling LHTES performance and chemical stability.

Sign in / Sign up

Export Citation Format

Share Document