From structure to multifunctional performance: Fibrous cellulose for advancing phase change materials

Fibrous cellulose has attracted significant attention as a stabilizing agent for PCMs, offering a pathway to next-generation energy materials that overcome the fluidity and leakage challenges of PCMs while contributing to carbon neutrality. Its unique properties, combined with excellent processability, enable the creation of advanced phase-change composites, unlocking innovative solutions for thermal management and environmental sustainability. Despite its rising prominence, the field lacks a comprehensive review on multifunctional fibrous cellulose PCM composites. Key aspects, such as integration techniques, structure-performance correlations, multifunctionality and the diverse applications of the fibrous cellulose-enhanced PCMs, remain insufficiently addressed, leaving critical gaps in the literature. This review aims to bridge these gaps by consolidating recent advancements in the utilization of fibrous cellulose for creating stabilized PCM composites. It systematically explores PCM stabilization strategies using fibrous cellulose, including kraft pulp and nanocellulose, while examining factors affecting structural and thermal regulation, multifunctional applications, and emerging innovations. Additionally, it examines research limitations, highlights new directions, and offers actionable insights for designing high-performance, multifunctional cellulose-based phase-change composites. By emphasizing the importance of structure-performance relationships when combining fibrous cellulose and PCM, this review seeks to inspire further exploration and innovation in this evolving field. • The review examines fibrous cellulose used for stable leak-proof confinement of PCMs. • It maps how fiber type and structure affect PCM confinement and storage performance. • It discusses pathways to scalable, circular, bio-based thermal energy storage systems.