{
  "abstract": "Artificial photosynthesis offers a promising route to close the anthropogenic carbon cycle, yet efficient photocatalytic CO2 conversion with H2O as an electron donor remains challenging.ZnTa2O6 (ZTO0.50) is one of the most active photocatalysts, but the origin of its activity remains unclear.In this study, we show that Ta-rich ZnTa2O6 (ZTOn, n = Zn/Ta) inherently contains a rutile-type tantalum oxide phase, identified as cationdeficient Ta0.8O2, whose role has been largely overlooked.By tuning the ZnO/Ta2O5 precursor ratio, we obtain ZTO0.43 with the highest Ta0.8O2 content.Structural and spectroscopic analyses reveal atomically intimate interfaces between Ta0.8O2 and ZnTa2O6 that promote charge separation and H2O oxidation.Density functional theory calculations show that Ta vacancies stabilise a semiconducting electronic structure and induce wavefunction localisation on adjacent O atoms, enhancing their reactivity towards H2O oxidation.Consequently, ZTO0.43 modified with the Ag@Cr cocatalyst achieves a CO formation rate exceeding 1 mmol h -1 , with a 95% selectivity; to the best of our knowledge, this is the highest CO formation rate obtained via photocatalytic conversion of CO2 with H2O as the electron donor.",
  "abstract_shown": true,
  "affiliations": [
    "Kyoto University",
    "Sumitomo Metal Mining (Japan)"
  ],
  "article_type": null,
  "arxiv": null,
  "author_total": 8,
  "authors": [
    {
      "affs": [
        0,
        1
      ],
      "name": "Kio Kawata"
    },
    {
      "affs": [
        0
      ],
      "name": "Shoji Iguchi"
    },
    {
      "affs": [
        0
      ],
      "name": "Shimpei Naniwa"
    },
    {
      "affs": [
        0
      ],
      "name": "Akihisa Ishikawa"
    },
    {
      "affs": [
        0
      ],
      "name": "Wataru Ota"
    },
    {
      "affs": [
        0
      ],
      "name": "Tohru Sato"
    },
    {
      "affs": [
        1
      ],
      "name": "Masamu Nishimoto"
    },
    {
      "affs": [
        0
      ],
      "name": "Kentaro Teramura",
      "orcid": "0000-0003-2916-4597"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/d8vwv1mc4tsnr.bib",
  "cited_by": 0,
  "doi": "10.26434/chemrxiv-2025-8x01k/v3",
  "fulltext_url": null,
  "id": "d8vwv1mc4tsnr",
  "issns": [],
  "landing_url": "https://chemrxiv.org/doi/full/10.26434/chemrxiv-2025-8x01k/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",
      "2105|Advanced Photocatalysis Techniques"
    ]
  ],
  "openalex": "W7220663848",
  "pdf_url": "https://chemrxiv.org/doi/pdf/10.26434/chemrxiv-2025-8x01k/v3",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-06",
  "publisher": "American Chemical Society (ACS)",
  "ris": "https://research.draconitic.com/paper/d8vwv1mc4tsnr.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:17:22Z",
      "native_id": "10.26434/chemrxiv-2025-8x01k",
      "source": "chemrxiv",
      "url": "https://chemrxiv.org/doi/full/10.26434/chemrxiv-2025-8x01k/v3"
    }
  ],
  "subjects": [
    {
      "field": "chemistry",
      "origin": "source:chemrxiv",
      "subfield": "general"
    }
  ],
  "title": "Cation-Deficient Tantalum Oxide–Zinc Tantalate Nanocomposite for Photocatalytic Carbon Dioxide Conversion",
  "title_text": "Cation-Deficient Tantalum Oxide–Zinc Tantalate Nanocomposite for Photocatalytic Carbon Dioxide Conversion",
  "type": "preprint",
  "updated_at": "2026-10-30T12:17:22Z",
  "url": "https://research.draconitic.com/paper/d8vwv1mc4tsnr",
  "venue": "ChemRxiv",
  "versions": []
}