{
  "abstract": "Nanodiamonds hosting luminescent point defects, known as fluorescent nanodiamonds (FND), are a leading platform for quantum technology. The nitrogen-vacancy (NV) centre is the most intensively studied of these; its negatively charged state (NV$^-$) can serve as a qubit at room temperature, and its stability is governed by surface functional groups. We present two solution-phase fluorination routes for stabilising NV$^-$: direct C-F bond formation by decarboxylation with xenon difluoride via a radical mechanism, and the Balz-Schiemann reaction, which replaces surface amino groups with fluorine. The two routes were compared by infrared, X-ray photoelectron, energy-dispersive X-ray, Raman and photoluminescence spectroscopy. Both gave a high NV$^-$ fraction, up to $\\sim$85% on average, which to our knowledge is among the highest reported for surface-terminated nanodiamonds of this size and, in particular, for fluorine termination. We attribute the stabilisation to the fluorination treatment, which removes acceptor-like carboxyl groups and forms C-F bonds that give the surface a positive electron affinity. Frequency-domain relaxometry shows that the fluorinated particles retain a long spin-lattice relaxation time, $733\\pm56$ and $712\\pm20$ $μ$s for the XeF$_2$ and Balz-Schiemann routes, several times the values reported for commercial HPHT nanodiamonds, although shorter than the $1173\\pm123$ $μ$s of the as-received material. Fluorination thus activates near-surface NV$^-$ centres, which dominate relaxometric sensing, at the cost of a moderate shortening of $T_1$.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2609.06605",
  "author_total": 7,
  "authors": [
    {
      "name": "Szabolcs Czene"
    },
    {
      "name": "Olga Krafcsik"
    },
    {
      "name": "Nikoletta Jegenyés"
    },
    {
      "name": "Dávid Beke"
    },
    {
      "name": "László Péter"
    },
    {
      "name": "Vladimir Verkhovlyuk"
    },
    {
      "name": "Adam Gali"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/5zqp12aq760xq.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2609.06605",
  "fulltext_url": null,
  "id": "5zqp12aq760xq",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2609.06605",
  "language": null,
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "http://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "cond-mat.mtrl-sci"
    ],
    [
      "arxiv",
      "quant-ph"
    ],
    [
      "openalex",
      "2505|Diamond and Carbon-based Materials Research"
    ]
  ],
  "openalex": "W7212045733",
  "pdf_url": "https://arxiv.org/pdf/2609.06605",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-22",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/5zqp12aq760xq.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:35:15Z",
      "native_id": "2609.06605",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2609.06605"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:cond-mat.mtrl-sci",
      "subfield": "condensed-matter"
    },
    {
      "field": "physics",
      "origin": "arxiv:quant-ph",
      "subfield": "quantum"
    }
  ],
  "title": "Solution-phase fluorination of nanodiamond: near-surface NV$^-$ activation and spin relaxation",
  "title_text": "Solution-phase fluorination of nanodiamond: near-surface NV^- activation and spin relaxation",
  "type": "preprint",
  "updated_at": "2026-10-30T12:35:15Z",
  "url": "https://research.draconitic.com/paper/5zqp12aq760xq",
  "venue": "arXiv",
  "versions": []
}