Metal-polyphenol based phase change microcapsules for photothermal conversion and storage

In this paper, a novel phase change microcapsules (MPN@PA) with metal-polyphenol (MPN) as shell material and paraffin (PA) as core material were prepared by interfacial self-assembly method. It has low preparation cost and shows excellent photothermal conversion and heat storage properties. The highest encapsulation rate of MPN@PA without leakage is 59.58% when the shell-core ration is 1.0:1.5. The morphology of MPN@PA is quasi-spheroid with the size of about 10∼26 μm. FT-IR and XRD analysis results show that MPN and PA are combined by hydrogen bonding, and no new substance is formed. The enthalpy of phase transformation of MPN@PA (1.0:1.5) is 140.9 J/g. Moreover, MPN@PA has excellent thermal stability, thermal reliability, photothermal conversion and heat storage efficiency (71.47%–73.31%). The prepared novel photothermal transformation microcapsule is expected to be applied to the high-efficiency storage, management and utilization of solar energy.