Zinc Nitrate Hexahydrate Pseudobinary Eutectics for Near-Room-Temperature Thermal Energy Storage.

Autor: Ahmed S; Department of Materials Science and Engineering, Texas A&M University, College Station, Texas 77843, United States., Ibbotson D; Department of Materials Science and Engineering, Texas A&M University, College Station, Texas 77843, United States., Somodi C; Department of Materials Science and Engineering, Texas A&M University, College Station, Texas 77843, United States., Shamberger PJ; Department of Materials Science and Engineering, Texas A&M University, College Station, Texas 77843, United States.
Jazyk: angličtina
Zdroj: ACS applied engineering materials [ACS Appl Eng Mater] 2023 Dec 20; Vol. 2 (3), pp. 530-541. Date of Electronic Publication: 2023 Dec 20 (Print Publication: 2024).
DOI: 10.1021/acsaenm.3c00444
Abstrakt: Stoichiometric salt hydrates can be inexpensive and provide higher volumetric energy density relative to other near-room-temperature phase change materials (PCMs), but few salt hydrates exhibit congruent melting behavior between 0 and 30 °C. Eutectic salt hydrates offer a strategy to design bespoke PCMs with tailored application-specific eutectic melting temperatures. However, the general solidification behavior and stability of eutectic salt hydrate systems remain unclear, as metastable solidification in eutectic salt hydrates may introduce opportunities for phase segregation. Here, we present a new family of low-cost zinc-nitrate-hexahydrate-based eutectics: Zn(NO 3 ) 2 ·6(H 2 O)-NaNO 3 ( T eu = 32.7 ± 0.3 °C; ΔH eu = 151 ± 6 J·g -1 ), Zn(NO 3 ) 2 ·6(H 2 O)-KNO 3 ( T eu = 22.1 ± 0.3 °C; ΔH eu = 140 ± 6 J·g -1 ), Zn(NO 3 ) 2 ·6(H 2 O)-NH 4 NO 3 ( T eu = 11.2 ± 0.3 °C; ΔH eu = 137 ± 5 J·g -1 ). While the tendency to undercool varies greatly between different eutectics in the family, the geologic mineral talc has been identified as an active and stable phase that dramatically reduces undercooling in Zn(NO 3 ) 2 ·6(H 2 O) and all related eutectics. Zn(NO 3 ) 2 ·6(H 2 O) and its related eutectics have shown stability for over a hundred thermal cycles in mL scale volumes, suggesting that they are capable of serving as robust and stable media for near-room-temperature thermal energy storage applications in buildings.
Competing Interests: The authors declare no competing financial interest.
(© 2023 American Chemical Society.)
Databáze: MEDLINE
Externí odkaz: