Biomass-based shape-stabilized phase change materials for thermal energy storage and multiple energy conversion

Phase change materials (PCMs) in solid-liquid form have the benefits of minimal volume alteration, high energy storage capacity, and appropriate phase transition temperature. They are capable of releasing and storing latent heat in a reversible manner to facilitate the storage and use of thermal energy during the transition process. However, solid-liquid PCMs still face some challenges, such as easy leakage in the molten state, low thermal conductivity and single function. To solve and avoid these problems, biomass-based materials as a kind of low price, wide source, mostly belong to porous media, are good carriers of PCMs. Biomass-supported composite phase change materials (CPCMs) effectively encapsulate PCMs by using the pore structure rich in biomass, improving the inherent defects of PCMs. In this review, the latest research achievement of biomass-based CPCMs in recent years is reviewed. Specifically, the treatment of biomass materials in CPCMs is first introduced, including raw biomass, biomass porous carbon materials and their derivatives. In addition, various approaches for improving the thermal characteristics (e.g., thermal conductivity and heat storage capacity) of biomass-based CPCMs were summarized. Additionally, we also present a series of typical applications of biomass-based CPCMs, such as energy conversion and thermal regulation, and the future research directions are prospected. This review will provide some guidance for promoting the research on biomass-based CPCMs, which is crucial for resource recycling and green and low-carbon development.