{
  "abstract": "Molten chloride salt is a widely studied high-temperature electrolyte, with established use in pyrochemical reprocessing and electrorefining, and frequent use as a model system for concentrated solar power and molten salt reactor applications. Chromium (Cr) is a key element in high-temperature structural alloys. However, the temperature-dependent evolution and stability of Cr species in this environment remain insufficiently understood. Cr-redox chemistry in molten chloride salts governs the dissolution, oxidation and transformation of Cr-containing species, with direct implications for corrosion and dealloying of structural alloys as well as broader molten-salt processing applications. In the present study, the chemical stability of CrCl 2 , CrCl 3 , and Cr 2 O 3 in LiCl-KCl eutectic molten salt during heating and cooling was systematically investigated using in-situ X-ray absorption spectroscopy. The results revealed that CrCl 3 and Cr 2 O 3 remained chemically stable under the tested conditions, whereas CrCl 2 underwent oxidation by impurities to form Cr 2 O 3 at 500 °C, but partially converted back to Cr 2+ species upon cooling to room temperature. Additional gas chromatography measurements detected H 2 evolution during heating of CrCl 2 in LiCl–KCl, supporting the involvement of residual moisture in the oxidation process. Additionally, the interaction between chromium and NiCl 2 in molten salt was examined, indicating that chromium likely reduced Ni 2+ to metallic Ni 0 , while being oxidized to Cr 2+ , which subsequently underwent a similar chemical evolution as CrCl 2 in the molten salt. These findings unravel a temperature-dependent, impurity-mediated redox cycle of Cr species between the initial room-temperature, molten, and post-cooling states in molten chloride salt, providing a foundation for understanding and controlling Cr the dissolution, oxidation and transformation, and for developing effective corrosion-mitigation strategies to enhance the stability of high-temperature structural alloys in molten-salt systems.",
  "abstract_shown": true,
  "affiliations": [
    "Department of Materials Science and Chemical Engineering",
    "Stony Brook University",
    "The Department of Chemistry",
    "Hunter College",
    "Brookhaven National Laboratory",
    "Chemistry Division",
    "Department of Chemistry",
    "University of Tennessee Knoxville",
    "Chemical Sciences Division",
    "Oak Ridge National Laboratory"
  ],
  "article_type": null,
  "arxiv": null,
  "author_total": 15,
  "authors": [
    {
      "affs": [
        0,
        1
      ],
      "name": "Yuxiang Peng",
      "orcid": "0000-0002-8688-3654"
    },
    {
      "affs": [
        0,
        1
      ],
      "name": "Kaifeng Zheng"
    },
    {
      "affs": [
        2,
        3
      ],
      "name": "Kazuhiro Iwamatsu"
    },
    {
      "affs": [
        0,
        1
      ],
      "name": "Ankita Mohanty"
    },
    {
      "affs": [
        4
      ],
      "name": "Denis Leshchev"
    },
    {
      "affs": [
        4
      ],
      "name": "Akhil Tayal"
    },
    {
      "affs": [
        4
      ],
      "name": "Jorge Moncada Vivas"
    },
    {
      "affs": [
        5,
        4
      ],
      "name": "Bobby Layne"
    },
    {
      "affs": [
        0,
        1
      ],
      "name": "Xiaoyin Zheng"
    },
    {
      "affs": [
        6,
        7
      ],
      "name": "Ellie Kim"
    },
    {
      "affs": [
        6,
        7,
        8,
        9
      ],
      "name": "Phillip Halstenberg"
    },
    {
      "affs": [
        6,
        7,
        8,
        9
      ],
      "name": "Sheng Dai"
    },
    {
      "affs": [
        5,
        4
      ],
      "name": "James F. Wishart"
    },
    {
      "affs": [
        0,
        1,
        5,
        4
      ],
      "name": "Anatoly I. Frenkel"
    },
    {
      "affs": [
        0,
        1,
        4
      ],
      "name": "Yu-chen Karen Chen-Wiegart"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/14wn24a3x3w8x.bib",
  "cited_by": 0,
  "doi": "10.26434/chemrxiv.15005212/v3",
  "fulltext_url": null,
  "id": "14wn24a3x3w8x",
  "issns": [],
  "landing_url": "https://chemrxiv.org/doi/full/10.26434/chemrxiv.15005212/v3",
  "language": null,
  "licence": "CC-BY",
  "licence_label": "CC BY",
  "licence_source": "journal",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "openalex",
      "1507|Molten salt chemistry and electrochemical processes"
    ]
  ],
  "openalex": "W7221748666",
  "pdf_url": "https://chemrxiv.org/doi/pdf/10.26434/chemrxiv.15005212/v3",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-13",
  "publisher": "American Chemical Society (ACS)",
  "ris": "https://research.draconitic.com/paper/14wn24a3x3w8x.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:17:24Z",
      "native_id": "10.26434/chemrxiv.15005212",
      "source": "chemrxiv",
      "url": "https://chemrxiv.org/doi/full/10.26434/chemrxiv.15005212/v3"
    }
  ],
  "subjects": [
    {
      "field": "chemistry",
      "origin": "source:chemrxiv",
      "subfield": "general"
    }
  ],
  "title": "Unraveling the Temperature-Dependent Redox Cycle of Chromium Species in Molten Chloride Salt via In-Situ X-ray Absorption Spectroscopy",
  "title_text": "Unraveling the Temperature-Dependent Redox Cycle of Chromium Species in Molten Chloride Salt via In-Situ X-ray Absorption Spectroscopy",
  "type": "preprint",
  "updated_at": "2026-10-30T12:17:24Z",
  "url": "https://research.draconitic.com/paper/14wn24a3x3w8x",
  "venue": "ChemRxiv",
  "versions": []
}