Efficient and Secure Encapsulation of a Natural Phase Change Material in Nanofibers Using Coaxial Electrospinning for Sustainable Thermal Energy Storage

Dev Patel; Wanying Wei; Harmann Singh; Kai Xu; Christopher Beck; Michael Wildy; John Schossig; Xiao Hu; Dong Choon Hyun; Wenshuai Chen; Ping Lu

doi:10.1021/acssuschemeng.3c02094

Efficient and Secure Encapsulation of a Natural Phase Change Material in Nanofibers Using Coaxial Electrospinning for Sustainable Thermal Energy Storage

ACS Sustain Chem Eng. 2023 Jul 27;11(31):11570-11579. doi: 10.1021/acssuschemeng.3c02094. eCollection 2023 Aug 7.

Authors

Affiliations

¹ Department of Chemistry and Biochemistry, Rowan University, Glassboro, New Jersey 08028, United States.
² Department of Physics and Astronomy, Rowan University, Glassboro, New Jersey 08028, United States.
³ Department of Polymer Science and Engineering, Kyungpook National University, Daegu 41566, South Korea.
⁴ Key Laboratory of Bio-based Material Science and Technology, Ministry of Education, Northeast Forestry University, Harbin 150040, China.

Abstract

In this study, we present an ecofriendly technique for encapsulating lauric acid (LA), a natural phase change material, within polystyrene (PS) nanofibers through coaxial electrospinning. The resulting LAPS core-sheath nanofibers exhibited a melting enthalpy of up to 136.6 J/g, representing 75.8% of the heat storage capacity of pristine LA (180.2 J/g), a value surpassing all previously reported core-sheath fibers. Scanning electron microscopy revealed uniform LAPS nanofibers free of surface LA until the core LA feed rate reached 1.3 mL/h. As the core LA feed rate increased, the fiber diameter shrank from 2.24 ± 0.31 to 0.58 ± 0.45 μm. Infrared spectra demonstrated a proportional increase in the LA content with rising core LA injection rates. Thermogravimetric analysis found the maximum core LA content in core-sheath nanofibers to be 75.0%. Differential scanning calorimetry thermograms displayed a trend line shift upon LA leakage for LA_1.3PS nanofibers. LAPS fibers containing 75.0% LA effectively maintained consistent cycling stability and reusability across 100 heating-cooling cycles (20-60 °C) without heat storage deterioration. The core LA remained securely within the PS sheath after 100 cycles, and the LAPS nanofibers retained an excellent structural integrity without rupture. The energy-dense and form-stable LAPS core-sheath nanofibers have great potential for various thermal energy storage applications, such as building insulation, smart textiles, and electronic cooling systems, providing efficient temperature regulation and energy conservation.