Thermal and Physical Characterization of PEG Phase Change Materials Enhanced by Carbon-Based Nanoparticles

This paper presents the preparation and thermal/physical characterization of phase change materials (PCMs) based on poly(ethylene glycol) 400 g·mol−1 and nano-enhanced by either carbon black (CB), a raw graphite/diamond nanomixture (G/D-r), a purified graphite/diamond nanomixture (G/D-p) or nano-Diamond nanopowders with purity grades of 87% or 97% (nD87 and nD97, respectively). Differential scanning calorimetry and oscillatory rheology experiments were used to provide an insight into the thermal and mechanical changes taking place during solid-liquid phase transitions of the carbon-based suspensions. PEG400-based samples loaded with 1.0 wt.% of raw graphite/diamond nanomixture (G/D-r) exhibited the lowest sub-cooling effect (with a reduction of ~2 K regarding neat PEG400). The influences that the type of carbon-based nanoadditive and nanoparticle loading (0.50 and 1.0 wt.%) have on dynamic viscosity, thermal conductivity, density and surface tension were also investigated in the temperature range from 288 to 318 K. Non-linear rheological experiments showed that all dispersions exhibited a non-Newtonian pseudo-plastic behavior, which was more noticeable in the case of carbon black nanofluids at low shear rates. The highest enhancements in thermal conductivity were observed for graphite/diamond nanomixtures (3.3–3.6%), while nano-diamond suspensions showed the largest modifications in density (0.64–0.66%). Reductions in surface tension were measured for the two nano-diamond nanopowders (nD87 and nD97), while slight increases (within experimental uncertainties) were observed for dispersions prepared using the other three carbon-based nanopowders. Finally, a good agreement was observed between the experimental surface tension measurements performed using a Du Noüy ring tensiometer and a drop-shape analyzer.

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A novel strategy for enhancing the thermal conductivity of shape-stable phase change materials via carbon-based in situ reduction of metal ions

Journal of Cleaner Production ◽

10.1016/j.jclepro.2019.118627 ◽

2020 ◽

Vol 243 ◽

pp. 118627 ◽

Cited By ~ 13

Author(s):

Yan Chen ◽

Han Ding ◽

Junkai Gao ◽

Xi Tang ◽

Yi Liu ◽

...

Keyword(s):

Thermal Conductivity ◽

Metal Ions ◽

Phase Change ◽

Phase Change Materials ◽

Stable Phase ◽

In Situ Reduction ◽

Novel Strategy ◽

Carbon Based

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Preparation and Experimental Evaluation of Phase-Change Characteristics in Carbon-Based Suspensions

Materials ◽

10.3390/ma11081315 ◽

2018 ◽

Vol 11 (8) ◽

pp. 1315 ◽

Cited By ~ 2

Author(s):

Tun-Ping Teng ◽

Ting-Chiang Hsiao ◽

Chun-Chi Chung

Keyword(s):

Thermal Conductivity ◽

Contact Angle ◽

Phase Change ◽

Phase Change Materials ◽

Sodium Dodecyl ◽

Sodium Dodecyl Benzene Sulfonate ◽

Freezing Temperature ◽

Combustion Method ◽

Change Characteristics ◽

Carbon Based

In this study, micro/nanocarbon-based materials (MNCBMs) were prepared using the high-pressure combustion method (HPCM) with an isoperibol oxygen bomb calorimeter at different oxygen pressures (0.5–3.0 MPa). The prepared MNCBMs were added to water to form carbon-based suspensions (CBSs); sodium dodecyl benzene sulfonate (SDBS) and defoamer were added to the CBSs to enhance their stability. The thermal conductivity, viscosity, density, and contact angle of the CBSs were measured using appropriate instruments to determine their fundamental characteristics. The phase-change characteristics of the CBSs were measured and analyzed using a differential scanning calorimeter (DSC) to evaluate the feasibility of employing them as phase-change materials in ice-storage air-conditioning systems. The results revealed that the maximal change ratios of thermal conductivity, viscosity, density, and contact angle of the samples were −3.15%, 6.25%, 0.23%, and −57.03%, respectively, as compared with the water. The CBS of S5 (oxygen pressure of 2.0 MPa) had the lowest melting temperature and subcooling degree (SD) and the highest freezing temperature in the experiments conducted using the DSC; thus, S5 was determined to be the most suitable CBS for use as a phase-change material of cold energy storage in this study.

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Thermo-physical characterization of some paraffins used as phase change materials for thermal energy storage

Journal of Thermal Analysis and Calorimetry ◽

10.1007/s10973-014-3775-6 ◽

2014 ◽

Vol 117 (2) ◽

pp. 557-566 ◽

Cited By ~ 32

Author(s):

E. M. Anghel ◽

A. Georgiev ◽

S. Petrescu ◽

R. Popov ◽

M. Constantinescu

Keyword(s):

Energy Storage ◽

Phase Change ◽

Thermal Energy ◽

Thermal Energy Storage ◽

Phase Change Materials ◽

Physical Characterization

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Thermal Conductivity Characterization of Nano-Enhanced Paraffin Wax

Volume 4: Energy Systems Analysis, Thermodynamics and Sustainability; Combustion Science and Engineering; Nanoengineering for Energy, Parts A and B ◽

10.1115/imece2011-65070 ◽

2011 ◽

Cited By ~ 1

Author(s):

Peter J. Sakalaukus ◽

Andrew Mosley ◽

Basil I. Farah ◽

Kuang-Ting Hsiao

Keyword(s):

Thermal Conductivity ◽

Energy Storage ◽

Phase Change ◽

Phase Change Materials ◽

Carbon Nanofiber ◽

Paraffin Wax ◽

Conductivity Enhancement ◽

Notable Increase ◽

Paraffin Waxes

Paraffin waxes are commonly used phase change materials for energy storage. However, the low thermal conductivity of the paraffin wax can limit the energy charging and discharging rate. In this research, a new nano-enhanced paraffin wax with dispersed conductive nanoparticles is tested for the thermal conductivity enhancement. A notable increase in the thermal conductivity has been measured from the carbon nanofiber enhanced paraffin wax.

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Experimental Evaluation of Fundamental and Phase Change Characteristics for Carbon-Based Suspensions

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.775.210 ◽

2018 ◽

Vol 775 ◽

pp. 210-216

Author(s):

Tun Ping Teng ◽

Ting Chiang Hsiao ◽

Chun Chi Chung

Keyword(s):

Thermal Conductivity ◽

Contact Angle ◽

Phase Change ◽

Air Conditioning ◽

Phase Change Materials ◽

Freezing Temperature ◽

Ice Storage ◽

Change Characteristics ◽

Air Conditioning Systems ◽

Carbon Based

In this study, carbon-based materials prepared using an isoperibol oxygen bomb calorimeter of varying oxygen pressure were added to water to form carbon-based suspensions (CBSs). The thermal conductivity, viscosity, density, and contact angle of CBSs were measured by appropriate instruments to understand the fundamental characteristics of CBSs. A differential scanning calorimeter (DSC) was used to measure and analyze the phase change characteristics of CBSs to evaluate the feasibility of employing CBSs as phase change materials (PCMs) in ice-storage air-conditioning systems. The experimental results revealed that the thermal conductivity, viscosity, and density of CBSs did not significantly change but a significant reduction in the contact angle of sample’s droplets occurred compared with that of water. The CBS of S5 had the lowest melting temperature and subcooling degree (SD) and highest freezing temperature in the DSC experiments; thus, S5 was determined to be the most suitable CBS for use as a PCM in this study.

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