Polyurethane template-based erythritol/graphite foam composite phase change materials with enhanced thermal conductivity and solar-thermal energy conversion efficiency.

In this paper, we report a kind of composite phase change materials (PCMs) fabricated by the vacuum impregnation method in which ER functions as the filter and graphite foams (GFs) serve as the supporting framework, which is fabricated from polyurethane (PU) foam. Polyvinyl alcohol (PVA) and multi-wall carbon nanotubes (MWCNTs) serve as modifiers. Compared with pure ER, the ER/GFs show an excellent performance improvement; the resulting supercooling degree was reduced by ∼59 °C and thermal conductivity was improved to 56.93 W m−1 K−1, more than 86-folds that of pure ER, resulting in a tremendous latent heat-releasing percentage enhancement of 77.09%. This demonstrates that such ER/GFs composites can be used for efficient solar-thermal energy conversion, and have a low supercooling degree, good leakage resistance, and high thermal conductivity, mitigating the severe issues of ER and presenting a new strategy for enhancing the solar energy storage performance. [Display omitted] • The MWCNTs modified GFs by the template method used in the solar-thermal conversion process. • The effects of MWCNTs modification with different mass fractions on the properties of GFs and ER/GFs were studied. • The template method was selected to prepare GFs to avoid the high-pressure foaming process traditionally. • The prepared ER/GF 0 has a high thermal conductivity of 56.93 W m−1 K−1. • The solar-thermal conversion and storage mechanism have been demonstrated. [ABSTRACT FROM AUTHOR]