{
  "abstract": "Bipolar membranes (BPM), composed of a cation exchange layer and an anion exchange layer, can enable steady-state operation at different pHs at the cathode and anode in electrolyzers. This enables the independent optimization of the cathode and anode catalysts for acidic and alkaline environments, respectively, which increases the scope for low-cost materials. Commercially available BPMs are operational only in a limited current range, therefore we aimed to develop custom BPMs for higher currents that are easily fabricated, mechanically stable, and suitable for storage in dry form. We used commercial single membranes combined with TiO 2 as the water dissociation catalyst in the junction, and have developed a hot-pressing method to prepare self-standing membranes that are mechanically robust, without a loss in electrochemical performance. Electrochemical Impedance Spectroscopy (EIS) was used to deconvolute the water dissociation resistance from other processes, leading to better understanding of the parameters that determine BPM performance. We demonstrate that the higher-performance BPMs surpass commercial BPMs for use in water electrolyzers, primarily due to a large decrease in the water dissociation overpotential to < 400 mV at 0.5 A cm -2 at 60 °C compared to ~1.3 V for the benchmark material. We also show how the membranes can be employed for high current density CO 2 electrolysis in a device structure that enable high CO 2 utilization efficiency, with the hot-pressed membranes achieving lower cell voltage and higher CO Faradaic efficiency compared to our previous reports with a custom BPM.",
  "abstract_shown": true,
  "affiliations": [
    "University of Liverpool",
    "Keele University"
  ],
  "article_type": null,
  "arxiv": null,
  "author_total": 4,
  "authors": [
    {
      "name": "Bhavin Siritanaratkul",
      "orcid": "0000-0003-0604-7670"
    },
    {
      "affs": [
        0,
        1
      ],
      "name": "Dora Alicia Garcia-Osorio"
    },
    {
      "affs": [
        0
      ],
      "name": "Veronica Hanna"
    },
    {
      "affs": [
        0
      ],
      "name": "Alexander Cowan"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/9bt7xm74mp4pk.bib",
  "cited_by": 0,
  "doi": "10.26434/chemrxiv-2025-c9n8r/v2",
  "fulltext_url": null,
  "id": "9bt7xm74mp4pk",
  "issns": [],
  "landing_url": "https://chemrxiv.org/doi/full/10.26434/chemrxiv-2025-c9n8r/v2",
  "language": null,
  "licence": "CC-BY-NC-ND",
  "licence_label": "CC BY-NC-ND",
  "licence_source": "journal",
  "licence_url": "https://creativecommons.org/licenses/by-nc-nd/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "openalex",
      "2204|Membrane-based Ion Separation Techniques"
    ]
  ],
  "openalex": "W7212170339",
  "pdf_url": "https://chemrxiv.org/doi/pdf/10.26434/chemrxiv-2025-c9n8r/v2",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-10",
  "publisher": "American Chemical Society (ACS)",
  "ris": "https://research.draconitic.com/paper/9bt7xm74mp4pk.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:17:19Z",
      "native_id": "10.26434/chemrxiv-2025-c9n8r",
      "source": "chemrxiv",
      "url": "https://chemrxiv.org/doi/full/10.26434/chemrxiv-2025-c9n8r/v2"
    }
  ],
  "subjects": [
    {
      "field": "chemistry",
      "origin": "source:chemrxiv",
      "subfield": "general"
    }
  ],
  "title": "Hot-pressed, mechanically stable bipolar membranes for water electrolysis and CO2 reduction",
  "title_text": "Hot-pressed, mechanically stable bipolar membranes for water electrolysis and CO2 reduction",
  "type": "preprint",
  "updated_at": "2026-10-30T12:17:19Z",
  "url": "https://research.draconitic.com/paper/9bt7xm74mp4pk",
  "venue": "ChemRxiv",
  "versions": []
}