{
  "abstract": "Plasmonic nanoparticles possess a strong optical absorption but suffer from low catalytic activity and limited sustainability. Here, we demonstrate that earth-abundant chalcopyrite CuFeS2 nanocrystals (NCs) can serve as a dual-functional platform benefitting from a strong polaritonic absorption enabling surfaceenhanced Raman scattering (SERS), and providing at the same time high activity for light-induced electrontransfer catalysis. The nanocrystals exhibit a prominent optical resonance at 500 nm, originating from interband transitions into a Fe 3d derived intermediate band that drives the dielectric function toward the Fröhlich condition. This localized resonance yields a SERS analytical enhancement factor of ~ 3×103 for 1,2-bis(4-pyridyl)ethylene (BPE), validated by Discontinuous Galerkin Time-Domain (DGTD) electrodynamic simulations and Density Functional Theory (DFT) calculations that motivates synergistic near-field and charge transfer contributions. In addition, the CuFeS2 NCs efficiently drive the selective photoconversion of p-nitrothiophenol (NTP) to 4,4′-dimercaptoazobenzene (DMAB). Crucially, wavelength-dependent SERS and kinetic measurements prove that both Raman amplification and surface reactivity follow the optical resonance profile. Power-dependent and substrate-heating controls further confirm that this reactivity is mediated by photoexcited electron transfer into adsorbate orbitals rather than photothermal heating. By integrating a polaritonic optical enhancement with long excited state lifetimes provided by the intermediate band electronic structure in a single earth-abundant material, this work establishes CuFeS2 nanocrystals as a versatile architecture for SERS diagnostics and non-thermal photochemistry.",
  "abstract_shown": true,
  "affiliations": [
    "Institute of Chemistry",
    "University of Potsdam",
    "AG Theoretische Optik & Photonik",
    "Humboldt-Universität zu Berlin",
    "Max-Born-Institute",
    "Institute of Physics and Astronomy",
    "Helmholtz Zentrum Berlin, Albert-Einstein-Str. 15, Berlin, Germany, 12489",
    "Dynamics of Molecules and Clusters Department, J. Heyrovský Institute of Physical Chemistry of the CAS, Dolejškova 3, Prague, Czech Republic, 18223"
  ],
  "article_type": null,
  "arxiv": null,
  "author_total": 13,
  "authors": [
    {
      "affs": [
        0,
        1
      ],
      "name": "Shashank K. Gahlaut",
      "orcid": "0000-0002-0956-8810"
    },
    {
      "affs": [
        0,
        1
      ],
      "name": "Biswajit Bhattacharyya"
    },
    {
      "affs": [
        2,
        3
      ],
      "name": "Guilherme Carraro Carella"
    },
    {
      "affs": [
        2,
        3,
        4
      ],
      "name": "Gino Wegner"
    },
    {
      "affs": [
        0,
        1
      ],
      "name": "Evgenii Titov"
    },
    {
      "affs": [
        5,
        1
      ],
      "name": "Felix Stete"
    },
    {
      "affs": [
        0,
        1
      ],
      "name": "Laura Baier"
    },
    {
      "affs": [
        0,
        1
      ],
      "name": "Radwan M. Sarhan"
    },
    {
      "affs": [
        0,
        1
      ],
      "name": "Peter Saalfrank"
    },
    {
      "affs": [
        0,
        1
      ],
      "name": "Andreas Taubert"
    },
    {
      "affs": [
        5,
        1,
        6
      ],
      "name": "Matias Bargheer"
    },
    {
      "affs": [
        2,
        3,
        4
      ],
      "name": "Kurt Busch"
    },
    {
      "affs": [
        0,
        1,
        7
      ],
      "name": "Ilko Bald"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/2rasd7xpqyzhs.bib",
  "cited_by": 0,
  "doi": "10.26434/chemrxiv.15007925/v2",
  "fulltext_url": null,
  "id": "2rasd7xpqyzhs",
  "issns": [],
  "landing_url": "https://chemrxiv.org/doi/full/10.26434/chemrxiv.15007925/v2",
  "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",
      "2504|Gold and Silver Nanoparticles Synthesis and Applications"
    ]
  ],
  "openalex": "W7204819418",
  "pdf_url": "https://chemrxiv.org/doi/pdf/10.26434/chemrxiv.15007925/v2",
  "pmcid": null,
  "pmid": null,
  "published": "2026-08-30",
  "publisher": "American Chemical Society (ACS)",
  "ris": "https://research.draconitic.com/paper/2rasd7xpqyzhs.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:17:17Z",
      "native_id": "10.26434/chemrxiv.15007925",
      "source": "chemrxiv",
      "url": "https://chemrxiv.org/doi/full/10.26434/chemrxiv.15007925/v2"
    }
  ],
  "subjects": [
    {
      "field": "chemistry",
      "origin": "openalex:2504|Gold and Silver Nanoparticles Synthesis and Applications",
      "subfield": "materials-polymers"
    }
  ],
  "title": "Light-Driven Electron-Transfer Catalysis on Earth-Abundant CuFeS2 Nanocrystals Probed by Operando SERS",
  "title_text": "Light-Driven Electron-Transfer Catalysis on Earth-Abundant CuFeS2 Nanocrystals Probed by Operando SERS",
  "type": "preprint",
  "updated_at": "2026-10-30T12:17:17Z",
  "url": "https://research.draconitic.com/paper/2rasd7xpqyzhs",
  "venue": "ChemRxiv",
  "versions": []
}