Fabrication of microencapsulated phase change materials based on n-octadecane core and silica shell through interfacial polycondensation

► We synthesize microencapsulated n-octadecane with silica wall via self-assembly. ► The microstructure of microcapsules depends strongly on the acidity of reaction. ► Compact silica shell is achieved when synthesis is carried out at pH 2.89. ► Good phase change properties can be achieved by controlling the pH value. ► The microcapsules obtain higher thermal conductivity due to their silica shell.