Study of thermo-physical properties and cycling stability of d-Mannitol-copper oxide nanocomposites as phase change materials. (February 2018)

• Record Type: Journal Article
• Authors: Salyan, Srikanth; Suresh, S.
• Is Part Of: Journal of energy storage. Volume 15(2018)
• Page Start: 245
• Page End: 255
• Publication Date: 2018-02
• Subjects: d-Mannitol -- Phase change materials -- Nanoparticles -- Thermal energy storage system -- Latent heat of fusion -- Latent heat of solidification -- Melting point and solidification point; Energy storage -- Periodicals; Energy storage -- Research -- Periodicals; 621.3126
• DOI: 10.1016/j.est.2017.10.013
• Languages: English
• ISSNs: 2352-152X

Abstract

Graphical abstract: Highlights: Characterisation ofd -Mannitol and Copper oxide nanoparticles as phase change material. Thermal cycling was done to check the stability of PCM after repeated cycles. Addition of CuO in DM enhaced crystallization during solidification process. The sub cooling effects decreased which confirms the increasing nucleating activity by nano-additives in DM. High latent heat ofd -Mannitol can reduce the total mass required in thermal energy storage devices. Abstract: Sugar alcohols (SA) are emerging as one of better energy storage materials for thermal energy storage (TES) application due to its phase change temperature ranges (−15 to 245 °C) and considerable phase change enthalpies of 100–430 kJ/kg. However, the main challenges include the low thermal response of the phase change materials (PCM) owing to its very low thermal conductivity values. In this study, d -Mannitol (DM)-copper oxide (CuO) nanocomposites (DM-CuON) were prepared using dispersion technique to form high thermal conductive nanocomposites. In this view, copper oxide (CuO) nanoparticles were mixed in DM in various mass fraction of 0.1, 0.2 and 0.5 wt.% using high-speed ball mill. Structural analysis was done by SEM and crystallography by XRD diffraction techniques. The XRD data reveal that the pure DM exhibited the polymorphic form of beta (β) phase. By varying the weight percentage from 0.1 to 0.5 wt.% the rate of relative crystallization increased as compared to pure DM. Thermal conductivity enhancement of 25.2% was observed for DM-CuON with 0.5 wt.%. It was observed that the interaction between CuO nanoparticles and DM were only physical in nature which confirmed its high chemical stability. After repeated heating/cooling cycles the heat of fusion decreased yet it showed high latent heat value of 256.20 kJ/kg, 252.48 kJ/kg, 246.85 kJ/kg and 240.78 kJ/kg after 50 cycles and 241.16 kJ/kg, 237.49 kJ/kg, 229.86 kJ/kg and 205.48 kJ/kg after 100 cycles for DM and DM-CuON. Mass changes observed were less than 3% after thermal cycling for a temperature range up to 250 °C. Overall CuO helps to achieve improved thermo-physical and heat storage characteristics for DM-CuON which suggest their potential candidate of usage in the medium temperature thermal energy storage system.