Leakage-resistant three-dimensional printable poly(vinyl alcohol)–sodium alginate encapsulated eicosane xerogels prepared via freeze-drying strategies for thermal energy storage
Journal of Energy Storage, cilt.177, 2026 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 177
- Basım Tarihi: 2026
- Doi Numarası: 10.1016/j.est.2026.123537
- Dergi Adı: Journal of Energy Storage
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Compendex, INSPEC
- Anahtar Kelimeler: 3D-printing, Freeze-drying, Phase change materials, Sustainable energy, Thermal energy storage, Xerogels
- Yıldız Teknik Üniversitesi Adresli: Evet
Özet
In this study, freeze-drying-based encapsulation strategies and three-dimensional (3D) printable poly(vinyl alcohol (PVA)/sodium alginate (SA)-encapsulated eicosane xerogels were developed for thermal energy storage (TES) applications. The xerogel composition was designed by changing PVA to SA solution ratios (2:1, 1:1, and 1:2 wt.:wt.) to determine the optimum formulation. To reduce eicosane leakage, vacuum impregnation and co-melting approaches were first evaluated, followed by investigations of eicosane loading capacity and 3D printability. According to the leakage test results (<0.6 wt%), the xerogel prepared at a 2:1 PVA:SA ratio with co-melting of eicosane exhibited the best performance. Due to its superior shape stability resulting from calcium chloride (CaCl2) based cross-linking, the PVA/SA encapsulated eicosane xerogel (C-TESC0-200) was successfully printed into customized geometries using melt deposition molding with 200 wt% eicosane and subsequently transferred into ultralight porous xerogels (32 mg/cm3) via lyophilization. Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA) confirmed the chemical compatibility, structural integrity, and thermal stability of the composites up to 200 °C. The TES properties showed melting and crystallization temperatures of 45.2 °C and 29.0 °C with latent heat values of −55.2 J/g and 62.91 J/g, respectively. In addition, the stability of eicosane encapsulation verified the stability after 200 thermal cycles, as confirmed by leakage tests, FTIR, and differential scanning calorimetry (DSC) results. Environmental evaluation using AGREE (0.87), AGREEMIP (0.91), and CO2 footprint indicators revealed that developed TES composites were environmentally friendly and compatible with green chemistry principles, together with a lower CO2 footprint. These findings demonstrate the cross-linked and 3D-printed PVA/SA-eicosane xerogel exhibited promising potential as sustainable TES materials with excellent leakage resistance and latent heat capacity for thermal management applications.