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DOE OSTI · 3682533

Synthesis and application of thermally responsive nanofiber coatings for overtemperature monitoring

Ihala Gamaralalage, Chanaka [ORNL] (ORCID:0000000214968886)·Jang, Seokhoon [ORNL] (ORCID:0000000291987853)·Meyer III, Harry [ORNL] (ORCID:0000000349941664)·Abdul Rahman, Nabihan [ORNL] (ORCID:0009000023830275)·Polo Garzon, Felipe [ORNL] (ORCID:0000000265076183)·Su, Yi Feng [ORNL]·Lin, Lianshan [ORNL] (ORCID:0000000203399219)·Armstrong, Beth [ORNL] (ORCID:0000000171493576)·Wang, Hsin [ORNL] (ORCID:0000000324269867)
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Abstract

This study presents a one-pot synthesis route to organometallic nanofibers based on copper thiolate, exhibiting distinctive chemical and physical characteristics. Electron microscopy analysis of morphology and composition revealed 2-10 μm-long, 50-90 nm-diameter hollow and non-hollow fibers composed of copper, sulfur, oxygen, hydrocarbon, and chlorine. Thermogravimetric analysis showed a pronounced mass loss within 120°C-135°C. To elucidate the thermal responsive pathways, the nanofibers were characterized before and after heating. X-ray photoelectron spectroscopy indicates that an initially mixed Cu(I)/Cu(II) oxidation states transition to predominantly Cu(I) upon heating. A layer of nanofiber was coated on battery pouch foil and evaluated as a candidate thermally sensitive coating. At elevated temperature (100-130°C), nanofiber coating released volatile organic compounds, sulfide and sulfur dioxide as detected using multiple gas sensors. This thermally responsive gas release/sensing approach provides a potential large-area temperature monitoring strategy, which is particularly relevant where direct temperature measurements of individual batteries is impractical. The results established proof of concept for nanofiber-coated battery pouch foil as overtemperature warning platform that can provide alerts when surface temperatures exceed a critical threshold. More broadly, the ability to form interconnected fiber networks positions copper thiolate nanofiber coatings as promising materials for advanced applications.

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BibTeXRIS

Ihala Gamaralalage, Chanaka [ORNL] (ORCID:0000000214968886), Jang, Seokhoon [ORNL] (ORCID:0000000291987853), Meyer III, Harry [ORNL] (ORCID:0000000349941664), Abdul Rahman, Nabihan [ORNL] (ORCID:0009000023830275), Polo Garzon, Felipe [ORNL] (ORCID:0000000265076183), Su, Yi Feng [ORNL], Lin, Lianshan [ORNL] (ORCID:0000000203399219), Armstrong, Beth [ORNL] (ORCID:0000000171493576), Wang, Hsin [ORNL] (ORCID:0000000324269867). 2026-08-01. Synthesis and application of thermally responsive nanofiber coatings for overtemperature monitoring. https://doi.org/10.1016/j.mtnano.2026.100932

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