In Situ Preparation of Polyethylene Glycol/ Silver Nanoparticles Composite Phase Change Materials with Enhanced Thermal Conductivity

Abstract Phase change materials (PCMs) have been widely used as efficient materials in latent heat thermal storage systems for various applications. The poor thermal conductivity of most organic PCMs, however, has long been considered as one of big obstacles hindering their practical applications. Here, we report the first example of in situ reduction of AgNO 3 precursor by PEG for preparation of polyethylene glycol/silver nanoparticles (PEG/Ag) PCMs nanocomposites with enhanced thermal conductivity only though a simple blending and heating process, without using any complicated techniques. The prepared Ag nanoparticles show a well dispersion in PEG matrix and the Ag is mainly existed in a zero of valence status. As expected, a maximum value of 211.7 % of that of pure PEG in thermal conductivities of the resulting PEG/Ag PCMs were achieved. The latent heat for PEG/Ag PCMs nanocomposites were evaluated in the range from 121.9 J g −1 to 141.9 J g −1 . Owing to high latent heat and excellent thermal conductivity, such PEG/Ag PCMs may have great potentials for energy saving applications. Especially, the in situ preparation of PEG/Ag makes it possible for site operation and scaled‐up production, which is of great technologically significance for realization of PCMs into real applications.