{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,25]],"date-time":"2026-09-25T02:24:39Z","timestamp":1790303079577,"version":"4.1.0"},"reference-count":32,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2023,2,21]],"date-time":"2023-02-21T00:00:00Z","timestamp":1676937600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"AdP CNR\u2014MiSE PT 22-24 \u201cProgetto Integrato Tecnologie di accumulo elettrochimico e termico\u201d"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>Ionic liquids (ILs) represent promising working fluids to be used in thermal energy storage (TES) technologies thanks to their peculiar properties, such as low volatility, high chemical stability, and high heat capacity. Here, we studied the thermal stability of the IL N-butyl-N-methylpyrrolidinium tris(pentafluoroethyl)trifluorophosphate ([BmPyrr]FAP), a potential working fluid for TES applications. The IL was heated at 200 \u00b0C for up to 168 h either in the absence or in contact with steel, copper, and brass plates to simulate the conditions used in TES plants. High-resolution magic angle spinning nuclear magnetic resonance spectroscopy was found to be useful for the identification of the degradation products of both the cation and the anion, thanks to the acquisition of 1H, 13C, 31P, and 19F-based experiments. In addition, elemental analysis was performed on the thermally degraded samples by inductively coupled plasma optical emission spectroscopy and energy dispersive X-ray spectroscopy. Our analysis shows a significant degradation of the FAP anion upon heating for more than 4 h, even in the absence of the metal\/alloy plates; on the other hand, the [BmPyrr] cation displays a remarkable stability also when heated in contact with steel and brass.<\/jats:p>","DOI":"10.3390\/ma16051762","type":"journal-article","created":{"date-parts":[[2023,2,22]],"date-time":"2023-02-22T01:39:47Z","timestamp":1677029987000},"page":"1762","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Ionic Liquids as Working Fluids for Heat Storage Applications: Decomposition Behavior of N-Butyl-N-methylpyrrolidinium tris(pentafluoroethyl)trifluorophosphate"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9793-1367","authenticated-orcid":false,"given":"Francesca","family":"Nardelli","sequence":"first","affiliation":[{"name":"Italian National Council for Research\u2014Institute for the Chemistry of OrganoMetallic Compounds, CNR-ICCOM, Via G. Moruzzi 1, 56124 Pisa, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8200-4301","authenticated-orcid":false,"given":"Enrico","family":"Berretti","sequence":"additional","affiliation":[{"name":"Italian National Council for Research\u2014Institute for the Chemistry of OrganoMetallic Compounds, CNR-ICCOM, Via Madonna del Piano 10, 50019 Firenze, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8098-2654","authenticated-orcid":false,"given":"Alessandro","family":"Lavacchi","sequence":"additional","affiliation":[{"name":"Italian National Council for Research\u2014Institute for the Chemistry of OrganoMetallic Compounds, CNR-ICCOM, Via Madonna del Piano 10, 50019 Firenze, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4260-3446","authenticated-orcid":false,"given":"Emanuela","family":"Pitzalis","sequence":"additional","affiliation":[{"name":"Italian National Council for Research\u2014Institute for the Chemistry of OrganoMetallic Compounds, CNR-ICCOM, Via G. Moruzzi 1, 56124 Pisa, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Angelo","family":"Freni","sequence":"additional","affiliation":[{"name":"Italian National Council for Research\u2014Institute for the Chemistry of OrganoMetallic Compounds, CNR-ICCOM, Via G. Moruzzi 1, 56124 Pisa, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1150-1551","authenticated-orcid":false,"given":"Silvia","family":"Pizzanelli","sequence":"additional","affiliation":[{"name":"Italian National Council for Research\u2014Institute for the Chemistry of OrganoMetallic Compounds, CNR-ICCOM, Via G. Moruzzi 1, 56124 Pisa, Italy"},{"name":"Centre for Instrument Sharing (CISUP), University of Pisa, Lungarno Pacinotti 43, 56126 Pisa, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,2,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Hauer, A. 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