{
  "abstract": "Controlling the emission color of bismuth oxyhalides (BiOX) remains a significant challenge, mainly because current strategies rely on multiple reagents, heterostructures, or energy-intensive synthetic routes. These approaches often disrupt the inherent structure-property relationship in these materials. In the current study, mixed bismuth oxyhalides (x = 0.0-1.0) were prepared using a simple acetate-assisted coprecipitation process. Glacial acetic acid regulated the release of Bi³⁺ ions while stabilizing the solution pH, which allowed controlled hydrolysis and halide incorporation. This strategy facilitated the preparation of BiOCl1-x Br x mixed-halides across the investigated compositional range (x = 0.0-1.0). All samples retained a tetragonal matlockite structure, matched with ICDD card No. 00-006-0249 (BiOCl) and 00-009-0393 (BiOBr), as confirmed by X-ray diffraction (XRD) analysis. As the Br⁻ content increased, the diffraction peaks shifted towards lower 2θ values. This is due to the replacement of smaller Cl⁻ ions (ionic radius = 1.81 Å) with larger Br⁻ ions (ionic radius = 1.96 Å), resulting in the gradual lattice expansion. To this effect, the lattice parameters increased from a = 3.90 Å and c = 7.41 Å (x = 0.0) to a = 3.97 Å and c = 8.31 Å (x = 1.0), indicating successful compositional modulation. It was observed that the Cl-rich sample (x = 0.0) exhibited thin flake-like morphology under scanning electron microscopy (SEM), whereas the Br-rich sample (x = 1.0) had more aggregated microplates. UV-vis spectroscopy revealed systematic tuning of the electronic structure, showing a gradual redshift of the absorption edge as the Br⁻ content increased. The band gap decreased from 2.70 eV to 2.18 eV, due to a stronger contribution of Br⁻ 4p orbitals to the valence band maximum. The formation of shoulders and broad absorption further explained the presence of Bi-Cl and Bi-Br bonding environments. The photoluminescence response was directly affected by these electronic changes. The emissions, including near-band-edge (∼330 nm), shallow, and deep defect emissions (∼420-480 nm), created a smooth color shift from blue to green-yellow. CIE chromaticity coordinates affirmed tunability of color with color purity exceeding 80 ± 5%. Based on optical analysis, a schematic band diagram shows an increase in the valence band with Br⁻ content. Overall, halide substitution in BiOCl1-x Br x controls lattice expansion, modulates band gap, and tunes emission color. The acetate-assisted hydrolysis methodology is thus a scalable platform for luminescent BiOCl1-x Br x materials without the use of surfactants or any external pH-regulator.",
  "abstract_shown": true,
  "affiliations": [
    "Department of Chemistry, COMSATS University Islamabad Abbottabad Campus-22060 Pakistan bushraismail@cuiatd.edu.pk afsahsaleem110@gmail.com amkhan@cuiatd.edu.pk +92 992 383595 +92 992 383592.",
    "Civil Engineering Department, El-Madina Higher Institute for Engineering and Technology Giza 12588 Egypt dr.ahmedkaram91@gmail.com."
  ],
  "article_type": "research article",
  "arxiv": null,
  "author_total": 4,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Afsah Saleem"
    },
    {
      "affs": [
        0
      ],
      "name": "Asad M Khan",
      "orcid": "0000-0002-5796-6573"
    },
    {
      "affs": [
        1
      ],
      "name": "Ahmad K Badawi",
      "orcid": "0000-0002-2075-653X"
    },
    {
      "affs": [
        0
      ],
      "name": "Bushra Ismail",
      "orcid": "0000-0002-0664-2894"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/f10dh8qd1qpm5.bib",
  "cited_by": 0,
  "doi": "10.1039/d6na00183a",
  "fulltext_url": "https://europepmc.org/articles/PMC13712237",
  "id": "f10dh8qd1qpm5",
  "issns": [
    "2516-0230"
  ],
  "landing_url": "https://europepmc.org/article/MED/42948703",
  "language": "eng",
  "licence": "CC-BY",
  "licence_label": "CC BY",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "heading",
      "Chemistry"
    ],
    [
      "openalex",
      "2505|Luminescence Properties of Advanced Materials"
    ]
  ],
  "openalex": "W7223848320",
  "pdf_url": "https://europepmc.org/articles/PMC13712237?pdf=render",
  "pmcid": "PMC13712237",
  "pmid": "42948703",
  "published": "2026-10-27",
  "publisher": "Royal Society of Chemistry",
  "ris": "https://research.draconitic.com/paper/f10dh8qd1qpm5.ris",
  "sources": [
    {
      "first_seen": "2026-10-31T00:20:33Z",
      "native_id": "MED:42948703",
      "source": "europepmc",
      "url": "https://europepmc.org/article/MED/42948703"
    },
    {
      "first_seen": "2026-10-31T12:22:51Z",
      "native_id": "PMC13712237",
      "source": "pmc",
      "url": "https://doi.org/10.1039/d6na00183a"
    }
  ],
  "subjects": [
    {
      "field": "chemistry",
      "origin": "openalex:2505|Luminescence Properties of Advanced Materials",
      "subfield": "materials-polymers"
    }
  ],
  "title": "Acetic acid-assisted controlled hydrolysis for Br-content-dependent emission color tuning in mixed-halide BiOCl1-x Br x systems.",
  "title_text": "Acetic acid-assisted controlled hydrolysis for Br-content-dependent emission color tuning in mixed-halide BiOCl1-x Br x systems.",
  "type": "peer-reviewed",
  "updated_at": "2026-10-31T12:22:51Z",
  "url": "https://research.draconitic.com/paper/f10dh8qd1qpm5",
  "venue": "Nanoscale advances",
  "versions": []
}