Facile functionalized mesoporous silica using biomimetic method as new matrix for preparation of shape‐stabilized phase‐change material with improved enthalpy

Dopamine-functionalized mesoporous silica (DPMS), which was prepared by using a facile, easy to operate, and environmentally friendly biomimetic method, was synthesized as a new supporter of polyethylene glycol (PEG) to prepare shape-stabilized phase-change material (ss-PCM) of PEG/DPMS with improved enthalpy. The thermal properties of PEG/DPMS were investigated, and the study results demonstrated that dopamine functionalization could regulate the crystallization property of PEG molecules immobilized in PEG/DPMS, and then the enthalpy of PEG/DPMS could be improved effectively. Compared with the ss-PCM of PEG/SBA-15 that was synthesized by using unfunctionalized silica molecular sieve (SBA-15) as the matrix, after dopamine modification, the fusion and solidification enthalpies of 70-wt% PEG/DPMS increased from 47.25 and 34.96 J/g to 69.77 and 67.54 J/g, respectively. The interaction mechanism study results suggested that the amino groups in the molecule of poly-dopamines on the surface of DPMS could interact with the oxygen atoms in the molecules of PEG to form hydrogen bonds. Additionally, the PEG/DPMS had favorable thermal reliability and prominent thermal stability. Hence, the DPMS could be applied as a promising supporter for the fabrication of ss-PCM.