Silver nanowire bridged graphene framework for encapsulating phase change materials with high thermal conductivity and solar-to-heat conversion ability

Abstract

To construct a high-efficiency thermally conductive graphene nanoplate (GNP) framework, ball-milling technique and silver nanowires (AgNW) bridging strategy were employed to improve the compatibility of GNP and the interfacial thermal resistance (ITR) in GNP skeletons, respectively. By using unidirectionally freeze casting technique, long range ordered GNP frameworks containing a small amount of AgNW as “bridge” were obtained, which were used to encapsulation phase change material (PCM). As a result, the honeycomb-like micropores of the framework with strong capillary effect give PCM anti-leakage and shape stability. The vertically aligned and AgNW bridged GNP skeletons form high-speed heat transfer paths endowith low ITR, thus significantly improve thermal conductivity to 7.24 W/mK. More importantly, GNP framework with strong light absorption ability endows PCM with well solar-to-heat conversion and storage ability. Therefore, AgNW bridged GNP framework endowing PCM with comprehensive thermal management ability exhibits a high potential in addressing the thermal problems of electronics.