Shape-Stabilized Phase Change Materials with Superior Thermal Conductivity for Thermal Energy Harvesting

This work presents the preparation of highly thermally conductive and shape-stabilized phase change composites (SSPCMs) at low filler loading. Polyethylene glycol (PEG) served as the phase change component. The high thermal conductivity is realized by the construction of dual thermally conductive networks based on boron nitride (BN) and expanded graphite (EG). The shape stabilization is obtained by the combined effects of the physical absorption of EG and the chemical crosslinking of epoxy. The prepared composite has a thermal conductivity of 3.907 W m(-1) K-1 at a low filler loading when filled with 6.00% EG and 16.00% BN. Correspondingly, the melting enthalpy and crystallization enthalpy can maintain 79.93 and 75.39 J g(-1), respectively. The result indicates that the prepared composite has excellent thermal stability and PEG is firmly stabilized in the composites, it would not leak from the matrix when exposed to high temperature and long heating periods. The experiment also confirms that the prepared composite has superior solar-thermal energy conversion and thermal management ability.

Automated summary

This work presents the preparation of highly thermally conductive and shape-stabilized phase change composites (SSPCMs) at low filler loading. The composite exhibits excellent thermal conductivity, stability, solar-thermal energy conversion, and thermal management ability.