One-pot synthesis of light-driven polymeric composite phase change materials based on N-doped porous carbon for enhanced latent heat storage capacity and thermal conductivity

2018 ◽  
Vol 179 ◽  
pp. 392-400 ◽  
Author(s):  
Dimberu G. Atinafu ◽  
Wenjun Dong ◽  
Xiubing Huang ◽  
Hongyi Gao ◽  
Jingjing Wang ◽  
...  
Processes ◽  
2021 ◽  
Vol 9 (12) ◽  
pp. 2191
Author(s):  
Su-Gwang Jeong ◽  
Taemin Lee ◽  
Jeonghun Lee

The application of phase change materials (PCMs) has been verified as an effective strategy for improving energy efficiency and reducing greenhouse gas emissions. Biocomposite PCMs (Bc-PCM) exhibit large latent heat, chemical stability, and a wide temperature range. In this study, thermal conductivity improved Bc-PCM (TBc-PCM) was made via vacuum impregnation with graphene nanoplatelets (GNPs). Chemical stability analysis and thermal performance analyses of the Bc-PCM and TBc-PCM were carried out as well as building energy simulations and thermal comfort analyses. Our results show Bc-PCM showed a higher heat storage capacity and enthalpy value compared to TBc-PCM. TBc-PCM exhibited a 378% increase in thermal conductivity compared to Bc-PCM. Building energy simulation results revealed that annual heating and cooling energy consumption decreased as the thickness of the PCM layer increased. In addition, the Bc-PCM with a larger PCM capacity was more effective in reducing energy consumption during the heating period. On the other hand, the cooling energy reduction effect was greater when TBc-PCM with high thermal conductivity was applied because of the high heat transfer during the cooling period. Thermal comfort evaluation revealed it was more comfortable when PCM was applied.


2017 ◽  
Vol 891 ◽  
pp. 509-515
Author(s):  
Jaroslav Jerz ◽  
Peter Tobolka ◽  
Martin Nosko ◽  
Tomáš Dvorák

The development of efficient materials for heat storage has become recently a popular research topic as amount of energy gained from solar power depends significantly on day and night cycle. That's why the right choice of material for heat storage directly affects the utilization efficiency of solar thermal energy. Research on heat storage materials nowadays focuses on phase change materials (PCMs) enabling repeatedly utilize the latent heat of the phase transition between the solid and liquid phase. Most currently used PCMs have low thermal conductivity, which prevents them from overcoming problem of rapid load changes in the charging and discharging processes. To overcome this obstacle and to obtain excellent heat storage possibility, various techniques have been proposed for enhancing the thermal conductivity of PCMs, such as adding metallic or nonmetallic particles, in-corporating of porous or expanded materials, fibrous materials, macro-, micro-, or nanocapsules, etc.The authors of this study report particularly the huge potential of oxide nanoadditives, such as titania (TiO2), alumina (Al2O3), silica (SiO2) and zinc oxide (ZnO), that are even in small quantities (up to 3 wt.%) able significantly to enhance the heat storage characteristics of conventional PCMs. Moreover, the microstructure of the granules produced by recycling of aluminum scrap refers to the possibility of their utilizing for the purpose of low cost solutions enabling to increase the thermal conductivity of PCMs. The above mentioned technical solutions are therefore the important keys to successful commercialization of materials for latent heat storage in future building industry.


2020 ◽  
Vol 142 (4) ◽  
Author(s):  
Pushpendra Kumar Singh Rathore ◽  
Shailendra Kumar Shukla ◽  
Naveen Kumar Gupta

Abstract Various properties of the paraffin have made them compatible to be incorporated in the building materials for improving the latent heat storage capacity of the building envelope. However, the poor thermal conductivity of the paraffin reduces their thermal performance and hence limits their direct application/incorporation in the buildings. In this study, composite mixtures of paraffin and expanded perlite (EP) with an equal weight percent of 49.5 and 47.5, loaded with 1% and 5% of graphene nano-platelets, respectively, were synthesized. The developed samples were characterized uncycled and after 2000 thermal cycles. The results indicate that phase change material (PCM)/expanded perlite/graphene nano-platelets composite shows a significant increment in the thermal conductivity, reduction in the latent heat storage capacity, and a small weight loss. The heat storage/release test depicts that the phase change material/expanded perlite/graphene nano-platelets-5 shows 1.66 and 2.5 times faster heat storage/release rate than phase change material/expanded perlite/graphene nano-platelets-1 and paraffin, respectively. There is no significant change noted after 2000 thermal cycles in phase change material/expanded perlite/graphene nano-platelets-5 and phase change material/expanded perlite/graphene nano-platelets-1 samples, suggesting long-term reliability of the composite PCM. Additionally, thermogravimetric analysis (TGA) and Fourier-transform infrared spectroscopy (FTIR) testing were also conducted and the results suggest high thermal reliability and good chemical compatibility. These analyses suggest that the phase change material/expanded perlite/graphene nano-platelets composite can become a potential candidate for thermal energy storage.


Sign in / Sign up

Export Citation Format

Share Document