Constructing cellulose nanocrystal/graphene nanoplatelet networks in phase change materials toward intelligent thermal management

The hybrid networks of cellulose nanocrystals (CNCs) and graphene nanoplatelets (GNPs) were constructed in polyethylene glycol (PEG) through the common solution compounding processing, in which GNPs provided the thermally conductive path while CNCs restricted the leakage of PEG during the phase transition. The results showed that CNCs greatly enhanced the shape stability of the composite phase change materials (PCMs) while thermal conductivity was still maintained at high level. At the contents of 8 wt% (CNCs) and 4 wt% (GNPs), the enthalpy of the composite PCM was 145.5 J/g, which was 88 % of pure PEG, and the thermal conductivity was 2.018±0.067 W/m K about 563.7 % higher than that of pure PEG. Furthermore, the composite PCMs exhibited outstanding light-thermal and electro-thermal conversion capabilities. Furthermore, the composite PCMs could be designed as the temperature stabilizing component exhibiting intelligent adaptive thermal management role, providing stable temperature condition for electronic devices in extreme environment.