Cellulosic scaffolds doped with boron nitride nanosheets for shape-stabilized phase change composites with enhanced thermal conductivity

Phase change materials (PCMs), widely used in thermal management filed, can store or release thermal energy during phase-changing processes, but the inherent low thermal conductivity and leakage problem restrict their practical applications. Herein, boron nitride nanosheets (BNNSs) doped cellulosic scaffolds (CS) were used as novel support materials to construct shape-stabilized PCM with enhanced thermal conductivity. The composite PCM exhibits excellent shape stability against pressure, tension and bending (90 degrees) even at high loading of the solid-liquid PCM polyethylene glycol (PEG) (95.6 wt%). The resulting composite PCMs have enthalpy capacity (Delta H-m/Delta H-c) ranged from 1653 J g(-1)/169.3 J g(-1) to 169.1 J g(-1)/ 176.1 J g(-1) with stable cycling reliability. Moreover, the thermal conductivity of the composite PCM could increase by 42.8% at a low loading of BNNSs (1.9 wt%), without affecting its electrical insulation properties (over 10(7) Omega cm). The thermally-conductive shape-stabilized PCM composite prepared by this feasible method have great potential in thermal management of electronics. (C) 2020 Elsevier B.V. All rights reserved