Highly thermal conductive and rechargeable 3D liquid metal network-based phase change composite enabling photothermal pad

This paper presents a liquid metal network-based phase change composite material (LM-PCM) with enhanced photothermal conversion and heat storage capability. In this work, the graphite flake@copper fillers are incorporated into LM to increase the thermal conductivity of metallic composite filler and increase the viscosity of LM-based composite. Hot-pressing method has been applied to construct highly thermal conductive LM network within PCM matrix. The surface of LM-PCM is spray-coated with graphite layer to collect solar energy and convert it into heat. The obtained LM-PCM exhibits thermal conductivity as high as ∼7 W/m·K with 50 vol% metallic filler and light absorption efficiency of ∼90%. Moreover, such LM-PCMs have been demonstrated to be thermally rechargeable, producing less pollution than the other disposable thermal pads. The development of LM-PCM shows great prospect as thermal comforting material for clinical therapy, and also provides a new solution for the application of LM-based composites.