Development and advancement of composite heat storage materials: Performance enhancement, functional optimization and material preparation of functional bionic phase change materials

At present, most performance improvement strategies for phase change materials (PCM) are mainly focused on single goal, while passively taking into account other properties, and lack active regulation of the coupling relationship and trade-off mechanism among multiple properties. In this review, the research progress on the performance enhancement, optimization, and preparation of PCM is summarized, and the concept of functional bionic PCM (FB-PCM) are proposed. Innovatively, FB-PCM is further discussed as an integrated design framework that links bio-inspired structural design, interfacial functional regulation, and process-oriented preparation, providing a new way to understand PCM research beyond isolated property enhancement. The issues that need to be urgently addressed in FB-PCM include: (1) the multi-performance design and structural integration of bionic PCM; (2) the functional group optimization mechanism of PCM performance under multiple constraints; (3) the digital-intelligent design and process-oriented preparation of PCM. In addition, the cross-scale integration mechanism of materials and devices also needs to be clarified. The first part of this review introduces the research progress of PCM performance enhancement and the current exploration of bionic strategies has also been reviewed. In the second part, the typical constraint relationships in the multi-performance optimization are summarized and the thermoelectric analogy is introduced as a new perspective for functional group screening in PCM. In the third part, typical PCM fabrication techniques are reviewed. Overall, this review not only summarizes recent progress, but also provides a framework-based perspective for moving PCM research from fragmented optimization toward more rational and integrated design.