Paraffin@Hectorite/water phase change fluid with sustainable suspension stability and efficient heat dissipation

Latent heat fluids (LHFs) suffer suspension stability challenges when used in cooling fields. Herein, hectorite with natural stable suspension are used to encapsulate paraffin and prepare microencapsulated phase change materials (MPCM), which were dispersed into liquid water to prepare microencapsulated phase change slurry (MPCS) with preferable suspension stability. It was found that the hectorite was electrostatic adsorbed onto the paraffin surface and formed a core-shell structure microcapsule. SEM (scanning electronic microscope) identified that MPCM exhibited a well-defined, core-shell structure with spherical morphology. DSC (differential scanning calorimeter) analysis demonstrated that phase change enthalpy of MPCM is 144.74 J/g with encapsulation efficiency of 61.45%. TGA (thermogravimetric analysis) revealed that hectorite contributed in improving the thermal stability of MPCM. It was observed that the MPCS could maintain stable suspension at least 30 days. The heat dissipation experiment showed that the MPCS with 5%, 8%, and 10% MPCM concentrations increased heat dissipation by 8.7%, 11.1%, and 13.7%, respectively, compared to pure water. This work reports a new strategy through introducing hectorite into phase change fluids to enhance suspension stability. The MPCS, with its preferable suspension stability and heat dissipation performance, has promising potential for applications in energy storage, cooling, and heat dissipation.