{
  "abstract": "A lead-free four-terminal tandem architecture is assessed by optically coupling a semi-transparent BaZr0.85Ti0.15S3 chalcogenide-perovskite top sub-cell to a Cu2ZnSn(S0.25Se0.75)4 (CZTSSe) bottom sub-cell. The assessment includes a 33.93% idealized design target only as an upper bound because the assumed p-type, low-defect top absorber has not been demonstrated in a photovoltaic device. The device physics are evaluated with a one-dimensional drift-diffusion framework based on the coupled Poisson and electron/hole continuity equations. A finite-volume Python implementation using Scharfetter-Gummel fluxes was benchmarked against a fresh SCAPS 3.3.08 single-junction calculation, giving differences of 0.842 mV in open-circuit voltage, 0.049 mA cm− 2 in short-circuit current density, and 0.056% point in fill factor; the J-V root-mean-square error was 0.169 mA cm− 2. The tandem parameter set was anchored to measured BaZrS3 thin-film transport and defect ranges and to a recent high-performance CZTSSe device. Under the favorable n-type top-absorber boundary, optical/electrical co-optimization moves the BaZr0.85Ti0.15S3 thickness from 0.90 μm to 0.05 μm and gives 3.30% from the top cell plus 13.56% from the filtered bottom cell, for a 16.86% four-terminal efficiency. A 1200-sample material/contact uncertainty analysis at this thickness gives P5, median, and P95 efficiencies of 8.07%, 10.73%, and 15.49%, respectively. An additional 55-case direct SCAPS sweep over donor density, bulk defect density, minority-hole mobility, and trap capture cross section, together with maximum-power-point depth profiles, identifies defect-mediated recombination and minority-hole collection as the controlling top-cell constraints. The results show that the proposed absorber pair remains scientifically interesting, but its performance is controlled by minority-hole transport, sulfur-vacancy-related n-type doping, top-cell thickness, bottom-cell material quality, and contact resistance. Accordingly, 33.93% should be interpreted as a long-term material-quality ceiling rather than an experimentally credible near-term prediction.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": null,
  "author_total": 6,
  "authors": [
    {
      "name": "Syed M. Hasnain",
      "orcid": "0000-0002-5102-3101"
    },
    {
      "name": "M. Amin Mir"
    },
    {
      "name": "Muhammad Waqar Ashraf"
    },
    {
      "name": "Abid Iqbal"
    },
    {
      "name": "Ali S. Alzahrani"
    },
    {
      "name": "Syed Hashim Raza Bukhari"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/5xhb0kfzmvwsh.bib",
  "cited_by": 0,
  "doi": "10.1038/s41598-026-74658-2",
  "fulltext_url": "https://doi.org/10.1038/s41598-026-74658-2",
  "id": "5xhb0kfzmvwsh",
  "issns": [
    "2045-2322"
  ],
  "landing_url": "https://www.nature.com/articles/s41598-026-74658-2",
  "language": "en",
  "licence": "CC-BY-NC-ND-4.0",
  "licence_label": "CC BY-NC-ND 4.0",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by-nc-nd/4.0",
  "metadata_licence": null,
  "native_subjects": [
    [
      "lcc",
      "Q"
    ],
    [
      "lcc",
      "R"
    ],
    [
      "openalex",
      "2208|Chalcogenide Semiconductor Thin Films"
    ]
  ],
  "openalex": "W7220456734",
  "pdf_url": "https://www.nature.com/articles/s41598-026-74658-2.pdf",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-05",
  "publisher": "Springer Science and Business Media LLC",
  "ris": "https://research.draconitic.com/paper/5xhb0kfzmvwsh.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:17:22Z",
      "native_id": "10.1038/s41598-026-74658-2",
      "source": "crossref",
      "url": "https://www.nature.com/articles/s41598-026-74658-2"
    },
    {
      "first_seen": "2026-10-30T13:45:54Z",
      "native_id": "9d3964ce24b74fca8145bdd5694acb12",
      "source": "doaj",
      "url": "https://doi.org/10.1038/s41598-026-74658-2"
    }
  ],
  "subjects": [
    {
      "field": "medicine",
      "origin": "lcc:R",
      "subfield": "general"
    }
  ],
  "title": "Experimentally informed drift-diffusion assessment of a lead-free four-terminal BaZr0.85Ti0.15S3/CZTSSe tandem solar cell",
  "title_text": "Experimentally informed drift-diffusion assessment of a lead-free four-terminal BaZr0.85Ti0.15S3/CZTSSe tandem solar cell",
  "type": "peer-reviewed",
  "updated_at": "2026-10-30T13:45:54Z",
  "url": "https://research.draconitic.com/paper/5xhb0kfzmvwsh",
  "venue": "Scientific Reports",
  "versions": []
}