Enhanced Thermal Energy Storage of n-Octadecane-Impregnated Mesoporous Silica as a Novel Shape-Stabilized Phase...

A series of n-octadecane/mesoporous silica (C₁₈/MS) shape-stabilized phase change materials (SSPCMs) with varying C₁₈ content were prepared, and the effects of adsorbed C₁₈ distributed within porous MS on the thermal properties were analyzed. As characterized, C₁₈ was first infiltrated into the mesoporous space, resulting in a SSPCM with a maximum of ∼52 wt % C₁₈. Additional adsorption of C₁₈ occurred on the external surface of MS. Consequently, the optimum 70 wt % C₁₈ SSPCM had no C₁₈ leakage and exhibited a heat storage capacity of 135.6 J/g and crystallinity of 83.5%, which were much larger than those of 52 wt % C₁₈ SSPCM (60.2 J/g and 68.2%, respectively). The prepared C₁₈/MS SSPCMs showed excellent thermal stability and thermal reliability up to 1000 accelerated thermal cycle tests. Moreover, the C₁₈/MS SSPCM incorporated in gypsum effectively reduced the temperature changes compared with the original gypsum, suggesting the promising application of the prepared C₁₈/MS SSPCM for energy-saving building applications.