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Tannic-acid-templated mesoporous silica nanoparticles (TAMSNs), which were synthesized using a simple, environmentally friendly, cost-effective, and nonsurfactant-based template method, were developed as a matrix for stearic acid to fabricate a novel shape-stabilized phase change material (SA/TAMSN). The characterization results showed that stearic acid was fully adsorbed on the TAMSNs by physical adsorption and the TAMSNs had no effect on the crystal structure of stearic acid. According to the DSC results, although the TAMSNs had a confinement effect on the activity of the stearic acid molecules, the fusion and solidification enthalpies of SA/TAMSN could reach 108.8 J g À1 and 114.1 J g À1, respectively.Additionally, the TGA thermograms indicated that there was no apparent weight loss from 20 C to 223 C for SA/TAMSN, which demonstrated that SA/TAMSNs have excellent thermal stability. All of the results suggested that the TAMSNs could be used as a promising matrix candidate for the shape stabilization of stearic acid.

Summary 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.