Design of a graphene oxide@melamine foam/polyaniline@erythritol composite phase change material for thermal energy storage

Abstract

At present, only a single modification method is adopted to improve the shortcomings of erythritol (ET) as a phase change material (PCM). Compared with a single modification method, the synergistic effect of multiple modification methods can endow ET with comprehensive performance to meet the purpose of package, supercooling reduction, and enhancement of thermal conductivity. In this work, we innovatively combine graphene oxide (GO) nanosheet modified melamine foam (MF) and polyaniline (PANI) to construct a novel ET-based PCM by blending and porous material adsorption modification. PANI as the nucleation center can enhance the crystallization rate, thereby reducing the supercooling of ET. Meanwhile, GO@MF foam can not only be used as a porous support material to encapsulate ET but also as a heat conduction reinforcement to improve heat storage and release rate. As a result, the supercooling of GO@MF/PANI@ET (GMPET) composite PCM decreases from 91.2 °C of pure ET to 57.9 °C and its thermal conductivity (1.58 W⋅m−1⋅K−1) is about three times higher than that of pure ET (0.57 W⋅m−1⋅K−1). Moreover, after being placed at 140 °C for 2 h, there is almost no ET leakage in the GMPET composite PCM, and the mass loss ratio is less than 0.75%. In addition, the GMPET composite PCM displays a high melting enthalpy of about 259 J⋅g−1 and a high initial mass loss temperature of about 198 °C. Even after the 200th cycling test, the phase transition temperature and the latent heat storage capacity of the GMPET PCM all remain stable. This work offers an effective and promising strategy to design ET-based composite PCM for the field of energy storage.