{
  "abstract": "Alkaline all-iron flow batteries offer a low-cost and inherently safe approach to large-scale energy storage, but Fe-complex anolytes remain limited by insufficient coordination stability, solubility, and utilization at high concentrations. Here, we develop a dual-ligand Fe(TEA)(PS) anolyte using triethanolamine as the primary ligand and pyridine-3-sulfonate (PS) as the secondary ligand. The secondary ligand reinforces the Fe coordination environment through pyridyl-N coordination while introducing a hydrophilic sulfonate group. Computational calculations and Fe K-edge X-ray absorption spectroscopy reveal an enlarged molecular configuration and a more saturated coordination environment. Fe(TEA)(PS) exhibits a reversible Fe(III)/Fe(II) redox couple at -0.87 V versus SHE and a solubility of 1.41 M in 2 M NaOH. The resulting full cell achieves 95.12% electrolyte utilization at 1.0 M and a peak power density of 422.8 mW cm -2 . It retains 98.28% of its capacity over 1200 cycles at 100 mA cm -2 . Moreover, a cell containing 0.8 M Fe(TEA)(PS) maintains 96.87% capacity after 1800 cycles, corresponding to a decay rate of only 0.0017% per cycle. These results establish second-ligand engineering as an effective strategy for developing stable, highly soluble, and highly utilized Fe-complex anolytes for alkaline all-iron flow batteries.",
  "abstract_shown": true,
  "affiliations": [
    "Department of Materials Science and Engineering, College of Design and Engineering",
    "National University of Singapore",
    "National University of Singapore (Suzhou) Research Institute, 377 Lin Quan Street, Suzhou, Jiangsu, China, 215123"
  ],
  "article_type": null,
  "arxiv": null,
  "author_total": 6,
  "authors": [
    {
      "affs": [
        0,
        1,
        2
      ],
      "name": "Heng Wang",
      "orcid": "0009-0002-4109-0156"
    },
    {
      "affs": [
        0,
        1
      ],
      "name": "Zhiyu Wang",
      "orcid": "0009-0008-4563-031X"
    },
    {
      "affs": [
        2
      ],
      "name": "Tianyu Yang"
    },
    {
      "affs": [
        2
      ],
      "name": "Hongtao Xie"
    },
    {
      "affs": [
        2
      ],
      "name": "Yingjia Hu"
    },
    {
      "affs": [
        0,
        1,
        2
      ],
      "name": "Qing Wang",
      "orcid": "0000-0002-0263-3579"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/6gkbnfm1yrj9m.bib",
  "cited_by": 0,
  "doi": "10.26434/chemrxiv.15009967/v1",
  "fulltext_url": null,
  "id": "6gkbnfm1yrj9m",
  "issns": [],
  "landing_url": "https://chemrxiv.org/doi/full/10.26434/chemrxiv.15009967/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 technologies research"
    ]
  ],
  "openalex": "W7220672733",
  "pdf_url": "https://chemrxiv.org/doi/pdf/10.26434/chemrxiv.15009967/v1",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-06",
  "publisher": "American Chemical Society (ACS)",
  "ris": "https://research.draconitic.com/paper/6gkbnfm1yrj9m.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:17:22Z",
      "native_id": "10.26434/chemrxiv.15009967",
      "source": "chemrxiv",
      "url": "https://chemrxiv.org/doi/full/10.26434/chemrxiv.15009967/v1"
    }
  ],
  "subjects": [
    {
      "field": "chemistry",
      "origin": "source:chemrxiv",
      "subfield": "general"
    }
  ],
  "title": "Dual-Ligand Engineering of a Stable and High-Utilization Iron Complex Anolyte for Alkaline All-Iron Flow Batteries",
  "title_text": "Dual-Ligand Engineering of a Stable and High-Utilization Iron Complex Anolyte for Alkaline All-Iron Flow Batteries",
  "type": "preprint",
  "updated_at": "2026-10-30T12:17:22Z",
  "url": "https://research.draconitic.com/paper/6gkbnfm1yrj9m",
  "venue": "ChemRxiv",
  "versions": []
}