Development of lithium hydroxide-metal organic framework-derived porous carbon composite materials for efficient low temperature thermal energy storage

Abstract

Lithium hydroxide based chemical heat storage (CHS) materials with high energy density and long storage periods have become the limelight of research for efficient use of low-temperature thermal energy and long-term storage. Herein, we report a novel LiOH composite CHS material with a porous carbon material derived from the zeolite imidazolate framework (ZIF-8) as supporting porous carbon matrix (ZSPCM). The Li/ZSPCM composite exhibits remarkable heat storage density up to 1373.3 kJ kg −1 with low charging temperature and good water adsorption ability owing to the large specific surface area of ZSPCM and well-dispersed small LiOH particles on it, which increase the contact between LiOH and H 2 O molecules and concomitant improvement in storage performance. In addition, the storage capacity of this composite material has no significantly degradation after 15 cycles of repeated hydration and dehydration, indicating its excellent cycle stability. And the thermal conductivity of Li/ZSPCM composite also shows a significant improvement over pristine LiOH by virtue of the outstanding thermal conductivity of the ZSPCM. This work develops a promising LiOH CHS material may sheds light on future directions for long period storage of low-temperature heat energy and the further exploitation of ZSPCM. • The chemical heat storage material based on the composite of LiOH·and porous carbon derived from ZIF-8 are developed. • Li/ZSPCM composite materials has remarkable heat storage density and good water adsorption ability. • Li/ZSPCM composite materials exhibits great cycling stability performance and significantly enhanced thermal conductivity.