Inorganic phase change materials in thermal energy storage: A review on perspectives and technological advances in building applications

Reutilization of thermal energy according to building demands constitutes an important step in a low carbon/green campaign. Phase change materials (PCMs) can address these problems related to the energy and environment through thermal energy storage (TES), where they can considerably enhance energy efficiency and sustainability. Concrete researches focusing on building materials revealed a vast potential of inorganic PCMs (iPCMs) utilization in thermal energy management systems particularly in the building applications as per literature; however, large but scattered literature is available on this research dimension. The current study presents an up-to-date review on iPCMs in the context of latent TES in the building sector: summarizing its performance, applications, and key challenges. The thermal performance of iPCMs is based on the higher heat storage capacity per unit volume together with lower cost value in contrast to other latent heat-based materials. However, several crucial challenges associated with iPCMs i.e., supercooling, encapsulation, phase separation, and corrosion issues are identified and discussed, which marginalize its performance in the progressive building applications. Furthermore, different proposed solutions to mitigate these issues are also comprehensively discussed. Likewise, passive and active integrations of iPCMs are systematically analyzed with building materials such as concrete, composites and novel structures with progressive technologies, most commonly used in buildings. In view of the actual challenges to building implementation, though the valuable research data on iPCMs is available in the literature, there still exist inconsistencies in both their fundamental research and development aspects and further real-scale applications. Hence, the current review addresses the profound insight into future perspectives based on the pertinent data of recent technological advances in this field.