▎ 摘　　要

A stearic acid (SA)/graphene composite microcapsule, having a core-shell structure, is prepared for the first time using a latex technology for use as a novel composite phase change material (PCM) for thermal energy management. Melted SA is dispersed in water using an anionic surfactant as a stabilizer and cooled to prepare a water-based latex containing negatively charged SA particles. A simple mixing of this latex with an aqueous dispersion of graphene, prepared with aid of a cationic surfactant, results in the self-assembly of graphene on a SA particle surface by an electrostatic interaction, allowing for the encapsulation of SA with graphene to form a core-shell composite microcapsule. The protective graphene shell gives an excellent shape stability to the composite during phase change and a substantial improvement in thermal stability of the active SA core. In addition, the core-shell structure contains a high weight fraction of the active core material due to the ultra-thin graphene shell having high thermal conductivity. This results in a high performance PCM with a large latent heat and an improved thermal conductivity. (C) 2015 Elsevier B.V. All rights reserved.