Synthesis and thermal performance of nano-sized paraffin-based titania encapsulated PCMs via sol–gel method

Paraffin- and titania (TiO 2 )-based nano-encapsulated phase change materials (NePCMs) were synthesized by the sol–gel process to improve thermal as well as phase change performance. Nine different samples of NePCMs were prepared by varying core/shell mass ratios, and their effect was investigated on thermal performance. The paraffin/TiO 2 nanocapsules were characterized by Fourier transform infrared spectrophotometer (FTIR), scanning electron microscopy (SEM), transmission electron microscope (TEM), X-ray diffraction (XRD), energy-dispersive X-ray (EDX), and dynamic light scattering (DLS). The characterization techniques confirmed that the paraffin was successfully contained in the TiO 2 shell. The maximum effective melting (73.47 Jg −1 ) and solidification (71.87 Jg −1 ) latent heat for the NePCMs were found to be at a 52.33% encapsulation ratio. The mean size of the NePCMs was approximately 238 nm measured from DLS. The thermal properties of the same sample stayed almost the same even after 100 thermal cycles validated by the differential scanning calorimetry (DSC) curves, and thermal stability was evaluated by a thermogravimetric analyzer (TGA). Graphical abstract