Insights into the roles of natural graphite in phase change materials

Abstract

Phase change materials (PCMs) that reversibly release or absorb thermal energy during phase transitions play a significant role in promoting renewable and sustainable energy development. However, the poor shape stability, low thermal conductivity, and inferior energy conversion efficiency of PCMs hinder their wider applicability and are difficult to meet the growing demand. As the precursor of carbon-based materials, including expanded graphite, graphene oxide, and graphene, natural graphite (NG) finds extensive applications and bring new potentials to the PCMs, enabling multiple cutting-edge thermal energy applications. Herein, we systematically discuss NG and its derivative-based composite PCMs for thermal energy storage, thermal energy conduction, and thermal energy conversion. This paper aims to offer insights into the roles of NG in PCMs and hope to provide a useful guide for the design of next-generation composite PCMs with high-energy-density, high thermal conductivity and high energy conversion efficiency.