Sanjeev Kumar Gupta, Soni Kumari, Ajay Pratap Singh
As global efforts have focused on innovative energy storage and management solutions, thermal energy storage (TES) systems have emerged as a key area of interest, driven by the unique capacity of phase change materials (PCMs) to efficiently store and release thermal energy during phase changes. However, traditional PCMs suffer from low thermal conductivity, supercooling, and phase segregation, which limit their practical application. This review explores recent advancements in nano-enhanced phase change materials (NEPCMs), which integrate nanoparticles such as metal oxides (e.g., Al 2 O 3 and CuO), carbon-based materials (e.g., graphene and carbon nano tubes), and hybrid nanostructures to overcome these limitations. Despite significant progress, a research gap persists in addressing nanoparticle agglomeration, long-term stability, and scalability for widespread adoption. The purpose of this evaluation was to consolidate recent developments, focusing on the synthesis, characterization, and applications of NEPCMs in thermal energy management systems. The objective was to evaluate how nanoparticles enhance PCM thermophysical properties while pinpointing obstacles and potential pathways for future research. The novelty of this review lies in consolidating the advancements in NEPCM synthesis, characterization, and applications, highlighting diverse nanomaterials and preparation techniques to enhance the thermophysical properties while identifying scalable, sustainable solutions for thermal management systems.The review concludes that NEPCMs significantly improve thermal performance, with examples such as 5 wt.% graphene nanoplatelets increasing thermal conductivity by 336% in bio-based PCMs and 1% SiO 2 -Al 2 O 3 enhancing specific heat by 57% in NaNO 3 -KNO 3 . However, challenges such as cost-effectiveness and environmental impact necessitate further research on hybrid nanostructures and bio-based PCMs for sustainable and scalable TES solutions.