{
  "abstract": "Sodium closo-hydridoborates have emerged as promising solid-state electrolytes for Na-ion batteries because of their high ionic conductivity and electrochemical stability. However, their sensitivity to water makes them challenging to scale-up. In this work, we systematically investigate the impact of controlled hydration on the structure, ion transport, and interfacial stability of an anion-mixed hydridoborate, Na4(B10H10)0.5(B12H12)0.5. By exposing the hydridoborate to varying degrees of relative humidity (RH) of 30-70%, we find that hydration at 30% enables retention of its moderate Na-ion conductivity (∼0.7 mS/cm) while higher hydration levels lead to the separation of the two anions ([B10H10] 2− and [B12H12] 2−), resulting in significant disruption in the Na ion conduction pathways. X-ray diffraction (XRD) and solid-state nuclear magnetic resonance (NMR) measurements indicate that hydration leads to the formation of distinct crystalline phases and alters the local ion coordination environments. The hydrated phase at 30% RH reversibly returns the original structure, restoring its ionic conductivity and compatibility with Na metal anodes. These findings provide insights into the role of structural water in Na-ion transport and a practical strategy for the use of moisturesensitive closo-hydridoborates solid state electrolytes.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": null,
  "author_total": 9,
  "authors": [
    {
      "name": "Hyeongjun Koh"
    },
    {
      "name": "Venkata Surya Chaitanya Kolluru"
    },
    {
      "name": "J. David Bazak"
    },
    {
      "name": "Yiteng Zheng"
    },
    {
      "name": "Tiffany L. Kinnibrugh"
    },
    {
      "name": "Bruce E. Koel"
    },
    {
      "name": "Timothy T. Fister"
    },
    {
      "name": "Maria K. Y. Chan"
    },
    {
      "name": "Kelsey B. Hatzell",
      "orcid": "0000-0002-5222-7288"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/af8gaemdy3x2t.bib",
  "cited_by": 0,
  "doi": "10.26434/chemrxiv.15009670/v1",
  "fulltext_url": null,
  "id": "af8gaemdy3x2t",
  "issns": [],
  "landing_url": "https://chemrxiv.org/doi/full/10.26434/chemrxiv.15009670/v1",
  "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",
      "2208|Advanced Battery Materials and Technologies"
    ]
  ],
  "openalex": "W7214888794",
  "pdf_url": "https://chemrxiv.org/doi/pdf/10.26434/chemrxiv.15009670/v1",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-29",
  "publisher": "American Chemical Society (ACS)",
  "ris": "https://research.draconitic.com/paper/af8gaemdy3x2t.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:17:21Z",
      "native_id": "10.26434/chemrxiv.15009670",
      "source": "chemrxiv",
      "url": "https://chemrxiv.org/doi/full/10.26434/chemrxiv.15009670/v1"
    }
  ],
  "subjects": [
    {
      "field": "chemistry",
      "origin": "source:chemrxiv",
      "subfield": "general"
    }
  ],
  "title": "Impact of Structural Water on Ionic Conductivity in Hydridoborates Solid Electrolytes",
  "title_text": "Impact of Structural Water on Ionic Conductivity in Hydridoborates Solid Electrolytes",
  "type": "preprint",
  "updated_at": "2026-10-30T12:17:21Z",
  "url": "https://research.draconitic.com/paper/af8gaemdy3x2t",
  "venue": "ChemRxiv",
  "versions": []
}