{
  "spore": "profile",
  "id": "bismuth-ferrite",
  "spore_version": "0.2",
  "family": "oxide-ceramics",
  "name": "Bismuth ferrite",
  "abbreviation": "BFO",
  "role": "multiferroic perovskite oxide (ferroelectric and antiferromagnetic at room temperature)",
  "category": "ceramics",
  "type": "oxides",
  "summary": "Bismuth ferrite (BiFeO3, BFO) is a perovskite oxide that is both ferroelectric and antiferromagnetic at room temperature. A 2020 open-access review gives its ferroelectric Curie temperature as 1103 K and its antiferromagnetic Neel temperature as 643 K. A supplier lists a density of 8.22 g/cm3 for the powder, and the one safety data sheet we read lists no hazard statements.\n",
  "best_for": "Research into room-temperature multiferroic devices, such as ferroelectric memory and ferroelectric photovoltaic test structures",
  "weakest_at": "Hard to make as a single phase: secondary phases and oxygen vacancies raise leakage current, and the hazard and thermal data are thin",
  "identity": {
    "formula": "BiFeO3",
    "cas": "12010-42-3",
    "crystal_system": "rhombohedral",
    "space_group": "R3c",
    "designations": [
      {
        "system": "Trade name",
        "code": "Bismuth iron oxide",
        "source": "samaterials-sds",
        "where": "Section 1, Trade Name"
      }
    ],
    "source": "alfa-bfo",
    "where": "Product page: CAS number 12010-42-3 and molecular formula BiFeO3; rhombohedral R3c structure from pmc-bfo-review, Crystal Structure of BFO section"
  },
  "tags": {
    "environments": [],
    "stresses": [],
    "applications": []
  },
  "properties": [
    {
      "benchmark": "curie_temperature",
      "label": "Ferroelectric Curie temperature",
      "value": 1103,
      "bound": "exact",
      "unit": "K",
      "scope": "material",
      "conditions": {
        "basis": "bulk ferroelectric phase transition, as quoted in the review together with its cited work",
        "form": "not stated in the review"
      },
      "method": "Value stated in an open-access review (it cites earlier work for it)",
      "status": "ground",
      "note": "Wikipedia (fetched in this run) gives approximately 1100K for the same transition; the review's 1103 K is recorded here.",
      "source": "pmc-bfo-review",
      "where": "Text in the crystal structure section, quoted as 'Curie temperature (TC) of 1103 K'",
      "source_detail": {
        "title": "Structure, Performance, and Application of BiFeO3 Nanomaterials",
        "id": "Nano-Micro Lett. 2020 Mar 28;12:81 (PMC7770668)",
        "url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC7770668/",
        "year": 2020,
        "kind": "paper",
        "license": "open access on PMC; licence not checked"
      }
    },
    {
      "benchmark": "neel_temperature",
      "label": "Antiferromagnetic Neel temperature (G-type)",
      "value": 643,
      "bound": "exact",
      "unit": "K",
      "scope": "material",
      "conditions": {
        "basis": "G-type antiferromagnetic transition, as quoted in the review together with its cited work"
      },
      "method": "Value stated in an open-access review (it cites earlier work for it)",
      "status": "ground",
      "note": "Wikipedia (fetched in this run) gives approximately 653 K; the review's 643 K is recorded here. The two differ by 10 K.",
      "source": "pmc-bfo-review",
      "where": "Text in the crystal structure section, quoted as 'Neel temperature (T N) of 643 K'",
      "source_detail": {
        "title": "Structure, Performance, and Application of BiFeO3 Nanomaterials",
        "id": "Nano-Micro Lett. 2020 Mar 28;12:81 (PMC7770668)",
        "url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC7770668/",
        "year": 2020,
        "kind": "paper",
        "license": "open access on PMC; licence not checked"
      }
    },
    {
      "benchmark": "lattice_constant_a",
      "label": "Lattice constant a, ceramic bulk (rhombohedral setting in the review)",
      "value": 5.63,
      "bound": "exact",
      "unit": "Å",
      "scope": "material",
      "conditions": {
        "form": "ceramic bulk",
        "temperature": "room temperature",
        "space_group": "R3c",
        "angle_in_same_sentence": "89.45 degrees"
      },
      "method": "Value stated in an open-access review",
      "status": "ground",
      "note": "Arxiv Table 1 gives a different experimental setting (a = 5.64 A with alpha = 59.42 deg), so the two cell descriptions are not interchangeable.",
      "source": "pmc-bfo-review",
      "where": "Text in the crystal structure section, quoted as 'lattice constant of a = 5.63 A'",
      "source_detail": {
        "title": "Structure, Performance, and Application of BiFeO3 Nanomaterials",
        "id": "Nano-Micro Lett. 2020 Mar 28;12:81 (PMC7770668)",
        "url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC7770668/",
        "year": 2020,
        "kind": "paper",
        "license": "open access on PMC; licence not checked"
      }
    },
    {
      "benchmark": "rhombohedral_angle",
      "label": "Rhombohedral angle, ceramic bulk",
      "value": 89.45,
      "bound": "exact",
      "unit": "°",
      "scope": "material",
      "conditions": {
        "form": "ceramic bulk",
        "temperature": "room temperature",
        "space_group": "R3c"
      },
      "method": "Value stated in an open-access review",
      "status": "ground",
      "source": "pmc-bfo-review",
      "where": "Text in the crystal structure section, quoted as 'rhombohedral angle of 89.45°'",
      "source_detail": {
        "title": "Structure, Performance, and Application of BiFeO3 Nanomaterials",
        "id": "Nano-Micro Lett. 2020 Mar 28;12:81 (PMC7770668)",
        "url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC7770668/",
        "year": 2020,
        "kind": "paper",
        "license": "open access on PMC; licence not checked"
      }
    },
    {
      "benchmark": "lattice_constant_a",
      "label": "Lattice constant a, experimental (Table 1 of the 2022 paper)",
      "value": 5.64,
      "bound": "exact",
      "unit": "Å",
      "scope": "material",
      "conditions": {
        "state": "pure BiFeO3, R3c phase",
        "temperature": "ambient temperature (as the table states)",
        "cell_setting": "rhombohedral, with alpha 59.42 deg"
      },
      "method": "Experimental value printed in a table of a 2022 arXiv paper, which cites an earlier source for it",
      "status": "ground",
      "source": "arxiv-2201.11161",
      "where": "Table 1, row a/Å, Expt. column",
      "source_detail": {
        "title": "Co-substituted BiFeO3: electronic, ferroelectric, and thermodynamic properties from first principles",
        "id": "arXiv:2201.11161",
        "url": "https://arxiv.org/pdf/2201.11161",
        "year": 2022,
        "kind": "paper",
        "license": "arXiv preprint, licence not checked"
      }
    },
    {
      "benchmark": "rhombohedral_angle",
      "label": "Rhombohedral angle, experimental (Table 1 of the 2022 paper)",
      "value": 59.42,
      "bound": "exact",
      "unit": "deg",
      "scope": "material",
      "conditions": {
        "state": "pure BiFeO3, R3c phase",
        "temperature": "ambient temperature (as the table states)",
        "cell_setting": "rhombohedral"
      },
      "method": "Experimental value printed in a table of a 2022 arXiv paper, which cites an earlier source for it",
      "status": "ground",
      "source": "arxiv-2201.11161",
      "where": "Table 1, row alpha/deg, Expt. column",
      "source_detail": {
        "title": "Co-substituted BiFeO3: electronic, ferroelectric, and thermodynamic properties from first principles",
        "id": "arXiv:2201.11161",
        "url": "https://arxiv.org/pdf/2201.11161",
        "year": 2022,
        "kind": "paper",
        "license": "arXiv preprint, licence not checked"
      }
    },
    {
      "benchmark": "band_gap",
      "label": "Band gap, thin films (experimental range)",
      "value": 2.6,
      "value_high": 2.8,
      "bound": "range",
      "unit": "eV",
      "scope": "material",
      "conditions": {
        "form": "thin films",
        "temperature": "ambient, as quoted"
      },
      "method": "Range quoted in a 2022 arXiv paper, which cites an earlier source; the paper says 'most commonly reported values for thin films range between 2.6 and 2.8 eV'",
      "status": "ground",
      "note": "The same paper gives 2.66 eV for pure BiFeO3 from another study (Peng et al.) without a stated test condition; that value is not recorded here.",
      "source": "arxiv-2201.11161",
      "where": "Introduction, paragraph on band gap; Table 1, row Eg/eV, Expt. column",
      "source_detail": {
        "title": "Co-substituted BiFeO3: electronic, ferroelectric, and thermodynamic properties from first principles",
        "id": "arXiv:2201.11161",
        "url": "https://arxiv.org/pdf/2201.11161",
        "year": 2022,
        "kind": "paper",
        "license": "arXiv preprint, licence not checked"
      }
    },
    {
      "benchmark": "remanent_polarization",
      "label": "Remnant ferroelectric polarization, thin film",
      "value": 55,
      "bound": "exact",
      "unit": "µC/cm2",
      "scope": "material",
      "conditions": {
        "form": "thin film",
        "note": "approximate value, printed with a tilde in the review"
      },
      "method": "Approximate value quoted in an open-access review, for the first BFO thin film it discusses",
      "status": "ground",
      "source": "pmc-bfo-review",
      "where": "Text on thin-film polarization, quoted as 'remnant ferroelectric polarization of Pr ~ 55 µC cm-2'",
      "source_detail": {
        "title": "Structure, Performance, and Application of BiFeO3 Nanomaterials",
        "id": "Nano-Micro Lett. 2020 Mar 28;12:81 (PMC7770668)",
        "url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC7770668/",
        "year": 2020,
        "kind": "paper",
        "license": "open access on PMC; licence not checked"
      }
    },
    {
      "benchmark": "remanent_polarization",
      "label": "Polarization along [111], bulk ceramic at 77 K",
      "value": 6.1,
      "bound": "exact",
      "unit": "µC/cm2",
      "scope": "material",
      "conditions": {
        "form": "bulk ceramic",
        "temperature": "77 K",
        "direction": "[111]"
      },
      "method": "Value quoted in an open-access review for a measurement it dates to the 1970s",
      "status": "ground",
      "source": "pmc-bfo-review",
      "where": "Text on ferroelectric hysteresis of BFO ceramic bulk, quoted as 'polarization value to be 6.1 µC cm-2 along the [111] direction at 77 K'",
      "source_detail": {
        "title": "Structure, Performance, and Application of BiFeO3 Nanomaterials",
        "id": "Nano-Micro Lett. 2020 Mar 28;12:81 (PMC7770668)",
        "url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC7770668/",
        "year": 2020,
        "kind": "paper",
        "license": "open access on PMC; licence not checked"
      }
    },
    {
      "benchmark": "spin_cycloid_period",
      "label": "Spin cycloid period along [111]",
      "value": 62,
      "value_high": 64,
      "bound": "range",
      "unit": "nm",
      "scope": "material",
      "conditions": {
        "direction": "[111]",
        "temperature": "not stated in the review"
      },
      "method": "Range quoted in an open-access review for the long-period spin cycloid of the G-type order",
      "status": "ground",
      "source": "pmc-bfo-review",
      "where": "Text on the G-type antiferromagnetic spin cycloid, quoted as '62-64 nm along the [111] direction'",
      "source_detail": {
        "title": "Structure, Performance, and Application of BiFeO3 Nanomaterials",
        "id": "Nano-Micro Lett. 2020 Mar 28;12:81 (PMC7770668)",
        "url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC7770668/",
        "year": 2020,
        "kind": "paper",
        "license": "open access on PMC; licence not checked"
      }
    },
    {
      "benchmark": "density",
      "label": "Density, powder (supplier listing)",
      "value": 8.22,
      "bound": "exact",
      "unit": "g/cm3",
      "scope": "material",
      "conditions": {
        "form": "crystalline powder, as listed by the supplier",
        "purity": "99.9%"
      },
      "method": "Supplier product page listing, printed as '8.22 g/cm3'; no measurement method given",
      "status": "ground",
      "note": "The Stanford Advanced Materials sheet for the same product prints Density as N/A, so this value comes from one supplier page only.",
      "source": "samaterials-bfo",
      "where": "Product specification table, Density row",
      "source_detail": {
        "title": "Bismuth ferrite (BiFeO3) powder, catalogue BI6032, Stanford Advanced Materials product page",
        "id": "catalogue BI6032; CAS 12010-42-3",
        "url": "https://powder.samaterials.com/bi6032-bismuth-ferrite-powder.html",
        "kind": "datasheet",
        "license": "supplier web page, cited not reproduced"
      }
    },
    {
      "benchmark": "density",
      "label": "Density, powder (second supplier listing)",
      "value": 8.22,
      "bound": "exact",
      "unit": "g/cm3",
      "scope": "material",
      "conditions": {
        "form": "powder, as listed by the supplier",
        "product": "CAS 12010-42-3"
      },
      "method": "Supplier product page listing, printed as '8.22 g/cm3'; no measurement method given",
      "status": "ground",
      "source": "alfa-bfo",
      "where": "Product properties list, Density",
      "source_detail": {
        "title": "Bismuth Ferrite, CAS 12010-42-3, Alfa Chemistry nanomaterials product page",
        "id": "catalogue ACM12010423; CAS 12010-42-3",
        "url": "https://nanomaterials.alfa-chemistry.com/product/bismuth-ferrite-cas-12010-42-3-306117.html",
        "kind": "web",
        "license": "supplier web page, cited not reproduced"
      }
    },
    {
      "benchmark": "melting_point",
      "label": "Melting point, powder (supplier listing)",
      "value": 1255,
      "bound": "exact",
      "unit": "°C",
      "scope": "material",
      "conditions": {
        "form": "powder, as listed by the supplier"
      },
      "method": "Supplier product page listing; the review and the 2022 paper print no melting point",
      "status": "ground",
      "source": "samaterials-bfo",
      "where": "Product specification table, Melting Point row",
      "source_detail": {
        "title": "Bismuth ferrite (BiFeO3) powder, catalogue BI6032, Stanford Advanced Materials product page",
        "id": "catalogue BI6032; CAS 12010-42-3",
        "url": "https://powder.samaterials.com/bi6032-bismuth-ferrite-powder.html",
        "kind": "datasheet",
        "license": "supplier web page, cited not reproduced"
      }
    },
    {
      "benchmark": "melting_point",
      "label": "Melting point, powder (second supplier listing)",
      "value": 1255,
      "bound": "exact",
      "unit": "°C",
      "scope": "material",
      "conditions": {
        "form": "powder, as listed by the supplier"
      },
      "method": "Supplier product page listing; no measurement method given",
      "status": "ground",
      "source": "alfa-bfo",
      "where": "Product properties list, Melting point",
      "source_detail": {
        "title": "Bismuth Ferrite, CAS 12010-42-3, Alfa Chemistry nanomaterials product page",
        "id": "catalogue ACM12010423; CAS 12010-42-3",
        "url": "https://nanomaterials.alfa-chemistry.com/product/bismuth-ferrite-cas-12010-42-3-306117.html",
        "kind": "web",
        "license": "supplier web page, cited not reproduced"
      }
    },
    {
      "benchmark": "molar_mass",
      "label": "Molar mass (PubChem computed)",
      "value": 312.82,
      "bound": "exact",
      "unit": "g/mol",
      "scope": "material",
      "conditions": {
        "basis": "computed by PubChem from the molecular formula BiFeO3"
      },
      "method": "Computed value in the PubChem compound record (PubChem release 2025.09.15)",
      "status": "calculated",
      "note": "The Stanford Advanced Materials sheet prints a molecular weight of 321.83 g/mol for the same product, which conflicts with this value; both are recorded in the story.",
      "source": "pubchem-bfo",
      "where": "Molecular Weight section of the compound record",
      "source_detail": {
        "title": "PubChem compound record, Bismuth ferrite (CID 161118030), PUG-View JSON",
        "id": "CID 161118030",
        "url": "https://pubchem.ncbi.nlm.nih.gov/rest/pug_view/data/compound/161118030/JSON",
        "year": 2025,
        "kind": "database",
        "license": "public domain (NCBI)"
      }
    }
  ],
  "corrosion": [
    {
      "environment": "Oxidizing agents and air (supplier safety data sheet)",
      "headline": "The supplier sheet lists oxidizing agents as reactive partners and gives no corrosion test.",
      "effect": "The sheet states the product is stable under recommended storage conditions, reacts with oxidizing agents, and gives metal oxide fume as its hazardous decomposition product. No corrosion, humidity or ageing test for bismuth ferrite was found in the sources we hold.",
      "rating": "unknown",
      "conditions": {
        "exposure": "supplier storage and reactivity statements",
        "test": "none found"
      },
      "source": "samaterials-sds",
      "where": "Section 10, Reactivity"
    }
  ],
  "risks": {
    "hazards": [
      {
        "text": "The Stanford Advanced Materials sheet for catalogue BI6032 (bismuth iron oxide, BiFeO3) prints Signal Word: None, Hazard Statements: None and Precautionary Statements: None. Its HMIS ratings are health 1, flammability 0 and physical 1.",
        "ghs": [],
        "source": "samaterials-sds",
        "where": "Section 2, Hazards Identification"
      },
      {
        "text": "The same sheet prints 'Median Lethal Dose: 4000 mg/kg for rat by mouth' and 'Potential Health Effects: May cause irritation' for eyes, skin, ingestion and inhalation.",
        "ghs": [],
        "source": "samaterials-sds",
        "where": "Section 11, Toxicological Information"
      },
      {
        "text": "PubChem's compound record for bismuth ferrite (CID 161118030) has no GHS classification section, so PubChem gives no GHS classification for this compound.",
        "ghs": [],
        "source": "pubchem-bfo",
        "where": "Compound record, list of sections (no Safety and Hazards section)"
      }
    ],
    "failure_risks": [
      {
        "mode": "Oxygen vacancies and secondary phases",
        "trigger": "Volatile bismuth and a changing iron valence during sintering or film growth",
        "consequence": "Sharply higher leakage current and difficulty obtaining a saturated ferroelectric hysteresis loop at room temperature.",
        "severity": "moderate",
        "source": "pmc-bfo-review",
        "where": "Text on leakage current and secondary phases"
      }
    ],
    "side_effects": [],
    "handling": [
      {
        "text": "Handle under dry protective gas and wash thoroughly after handling. Store in a cool dry place in a tightly sealed container under dry inert gas.",
        "source": "samaterials-sds",
        "where": "Section 7, Handling and Storage"
      },
      {
        "text": "The sheet prints 'Threshold Limit Value: 1 mg/m3 as Fe, long-term value' and recommends a dust respirator, rubber gloves, and safety glasses or goggles.",
        "source": "samaterials-sds",
        "where": "Section 8, Exposure Controls and Personal Protection"
      },
      {
        "text": "For spills, the sheet advises a HEPA filter vacuum and says to take care not to raise dust.",
        "source": "samaterials-sds",
        "where": "Section 6, Accidental Release Measures"
      }
    ],
    "mitigations": [
      {
        "text": "Ion substitution and solid solutions with other perovskite oxides are the most effective methods to suppress high leakage current, according to the review.",
        "source": "pmc-bfo-review",
        "where": "Text on leakage current, ion substitution"
      }
    ]
  },
  "uses": [
    {
      "application": "electronics-and-chips",
      "device": "Nonvolatile ferroelectric memory (research prototypes)",
      "example": "The review says BFO-based nanomaterials have both ferroelectricity and ferromagnetism at room temperature, which gives them great potential in high-density ferroelectric devices such as nonvolatile memories.",
      "source": "pmc-bfo-review",
      "where": "Section For Electronics"
    },
    {
      "application": "electronics-and-chips",
      "device": "Ferroelectric photovoltaic devices (research)",
      "example": "The review says the photovoltaic effect of ferroelectric nanomaterials depends on domain structure, polarization direction and band gap, and that BFO is studied for it.",
      "source": "pmc-bfo-review",
      "where": "Text on the photovoltaic effect of ferroelectric nanomaterials"
    }
  ],
  "supply": [
    {
      "subject": "Bismuth",
      "abundance": "Rarely mined as a primary product. Bismuth is mostly a byproduct of lead ore processing, and the USGS estimates world production at 16,000 tons in 2025.",
      "producers": [
        {
          "country": "China",
          "share_percent": 88,
          "year": 2025
        }
      ],
      "critical_lists": [
        {
          "list": "USGS 2025 List of Critical Minerals",
          "listed": true
        }
      ],
      "recycling": "USGS: recycled bismuth-containing alloy scrap was estimated to compose up to 10% of U.S. bismuth apparent consumption for 2021 to 2025.",
      "substitutes": [
        "USGS: bismuth compounds can be replaced in pharmaceutical applications by alumina, antibiotics, calcium carbonate and magnesia. The chapter does not discuss ferroelectric oxides."
      ],
      "source": "usgs-mcs2026-bismuth",
      "where": "Events, Trends and Issues; World Refinery Production and Capacity table (2025, China 88% of world production); Recycling; Substitutes"
    }
  ],
  "media": [],
  "documents": [
    {
      "title": "Safety Data Sheet: Bismuth Iron Oxide (Stanford Advanced Materials, catalogue BI6032)",
      "type": "sds",
      "url": "https://www.samaterials.com/tds/sc/1752820091-BI6032.pdf",
      "year": 2015
    },
    {
      "title": "PubChem compound record: Bismuth ferrite (CID 161118030)",
      "type": "database",
      "url": "https://pubchem.ncbi.nlm.nih.gov/compound/161118030",
      "year": 2025
    },
    {
      "title": "Structure, Performance, and Application of BiFeO3 Nanomaterials (open access)",
      "type": "paper",
      "url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC7770668/",
      "year": 2020
    },
    {
      "title": "Co-substituted BiFeO3: electronic, ferroelectric, and thermodynamic properties from first principles (arXiv)",
      "type": "paper",
      "url": "https://arxiv.org/pdf/2201.11161",
      "year": 2022
    },
    {
      "title": "Mineral Commodity Summaries 2026: Bismuth (USGS)",
      "type": "report",
      "url": "https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-bismuth.pdf",
      "year": 2026
    }
  ],
  "gaps": [
    "No flight, vacuum, radiation, thermal-vacuum or other space-environment result for bismuth ferrite was found, so the environments and applications tags are empty.",
    "The density and melting point come only from two supplier product pages. The Stanford Advanced Materials sheet prints Density and Melting Point as N/A, and no peer-reviewed density or melting point was found in the sources we hold.",
    "The molecular weight conflicts: PubChem computes 312.82 g/mol, while the Stanford Advanced Materials sheet prints 321.83 g/mol. Both are recorded in the story.",
    "The safety data sheet prints CAS as NIL, while the supplier product pages, Wikipedia and PubChem name CAS 12010-42-3. The CAS number is taken from the product page.",
    "PubChem gives no GHS classification for this compound. Only one supplier safety data sheet was read, and it lists no hazard statements.",
    "The band gap value comes from a 2022 first-principles paper that quotes earlier experiments; no primary measurement paper was read.",
    "The two lattice descriptions use different cell settings (a of 5.63 A with 89.45 deg in the review, and a of 5.64 A with alpha of 59.42 deg in the 2022 paper). Both are recorded.",
    "The Neel and Curie temperatures differ slightly between the review (643 K and 1103 K) and Wikipedia (approximately 653 K and approximately 1100K). The review's values are recorded and the difference is noted on each row.",
    "No corrosion, humidity, ageing or chemical-resistance test for bismuth ferrite was found in the sources we hold.",
    "The EU critical raw materials list status of bismuth was not checked in this run.",
    "No designation such as UNS, EN or ASTM applies to this oxide. The only other name is the supplier trade name Bismuth iron oxide from the safety data sheet.",
    "Atomic weights are left out of the recipe because no fetched source prints them for each element.",
    "The uses are research devices described in a review. No device performance number for a memory or photovoltaic device was found in the sources we hold.",
    "Several properties use short snake_case benchmark names that are not in the canonical list: lattice_constant_a, rhombohedral_angle, neel_temperature, band_gap, remanent_polarization, spin_cycloid_period and molar_mass."
  ],
  "story": {
    "why": "Bismuth ferrite (BiFeO3, BFO) is a perovskite oxide that is ferroelectric and antiferromagnetic at room temperature, which makes it a multiferroic. An open-access review gives its ferroelectric Curie temperature as 1103 K and its antiferromagnetic Neel temperature as 643 K, both far above room temperature. The material is studied for nonvolatile memory and ferroelectric photovoltaic devices, and most of the work so far is in films and ceramics rather than in finished products.",
    "uses": [
      {
        "where": "Nonvolatile memory research",
        "line": "The review says BFO-based nanomaterials show ferroelectricity and ferromagnetism at room temperature, which gives them potential in high-density ferroelectric devices such as nonvolatile memories. This is a research direction, not a product."
      },
      {
        "where": "Ferroelectric photovoltaic research",
        "line": "The review says the photovoltaic effect of ferroelectric nanomaterials depends on domain structure, polarization direction and band gap. A 2022 paper gives a thin-film band gap of 2.6 to 2.8 eV."
      }
    ],
    "can_do": [
      {
        "label": "Ferroelectric transition",
        "line": "The ferroelectric Curie temperature is 1103 K, according to the review. That is far above room temperature.",
        "benchmark": "curie_temperature",
        "scope": "material"
      },
      {
        "label": "Magnetic order",
        "line": "The Neel temperature is 643 K. Below it the iron moments order in a G-type antiferromagnetic pattern with weak magnetization from canting.",
        "benchmark": "neel_temperature",
        "scope": "material"
      },
      {
        "label": "Polarization",
        "line": "The review quotes a remnant polarization of about 55 µC/cm2 for a thin film. For a bulk ceramic it quotes 6.1 µC/cm2 along [111] at 77 K, a value from a 1970s measurement.",
        "scope": "material",
        "value": "About 55 µC/cm2 in a thin film; 6.1 µC/cm2 along [111] in a bulk ceramic at 77 K"
      },
      {
        "label": "Band gap",
        "line": "Thin films have a band gap of 2.6 to 2.8 eV, the range most often reported according to a 2022 paper that cites earlier experiments.",
        "scope": "material",
        "value": "2.6 to 2.8 eV for thin films"
      },
      {
        "label": "Density",
        "line": "A supplier lists a density of 8.22 g/cm3 for its powder. This is a listed value, and the second safety data sheet gives no density.",
        "scope": "material",
        "value": "8.22 g/cm3 for the powder (supplier)"
      }
    ],
    "compare": "The sources we hold do not compare bismuth ferrite with other materials directly, so this profile compares the figures for this material only. Its transition temperatures sit far above room temperature (Curie 1103 K, Neel 643 K), and its thin-film band gap is 2.6 to 2.8 eV. Its density of 8.22 g/cm3 and melting point of 1255 °C come from supplier pages, and the molecular weight conflicts, at 312.82 g/mol from PubChem against 321.83 g/mol from the supplier sheet.",
    "compare_rows": [
      {
        "label": "Ferroelectric Curie temperature",
        "benchmark": "curie_temperature",
        "scope": "material"
      },
      {
        "label": "Antiferromagnetic Neel temperature",
        "benchmark": "neel_temperature",
        "scope": "material"
      },
      {
        "label": "Density (powder, supplier)",
        "benchmark": "density",
        "scope": "material"
      }
    ],
    "handling": [
      "Handle under dry protective gas and wash thoroughly after handling, according to the supplier sheet.",
      "Store in a cool dry place in a tightly sealed container under dry inert gas, apart from oxidizing agents.",
      "Wear a dust respirator, rubber gloves, and safety glasses or goggles, and avoid raising dust.",
      "For spills, use a HEPA filter vacuum."
    ],
    "good_for": [
      "Research into ferroelectric memory and photovoltaic test devices, where room-temperature multiferroic behaviour is the point.",
      "High transition temperatures: the Curie temperature is 1103 K and the Neel temperature is 643 K."
    ],
    "watch_out": [
      "Secondary phases and oxygen vacancies make single-phase material hard to prepare, and they raise leakage current.",
      "Thin-film and bulk values differ: the remnant polarization is about 55 µC/cm2 in a thin film, but 6.1 µC/cm2 in a bulk ceramic at 77 K.",
      "The molecular weight conflicts (312.82 g/mol from PubChem, 321.83 g/mol from the supplier sheet), and the density and melting point come only from supplier pages."
    ],
    "verdict": "Bismuth ferrite is a research material with transition temperatures far above room temperature. Its one supplier safety data sheet lists no hazard statements, and no space data were found.",
    "recipe": {
      "line": "Bismuth ferrite is a perovskite oxide with the formula BiFeO3, which holds one bismuth atom, one iron atom and three oxygen atoms per formula unit. The supplier lists it as a crystalline perovskite powder, and the review gives its room-temperature structure as rhombohedral in space group R3c.",
      "parts": [
        {
          "name": "Bismuth",
          "symbol": "Bi",
          "role": "Sits on the large cation site. Its lone pair of electrons shifts the bismuth ion off centre, which creates the ferroelectric polarization along the [111] direction, per the review."
        },
        {
          "name": "Iron",
          "symbol": "Fe",
          "role": "Sits on the smaller cation site. Its magnetic moments order antiferromagnetically in a G-type pattern below the Neel temperature."
        },
        {
          "name": "Oxygen",
          "symbol": "O",
          "role": "Forms the oxygen octahedra around the iron, which hold the framework together and respond to the bismuth shift."
        }
      ]
    },
    "risk_groups": [
      {
        "title": "For people",
        "lead": "The one safety data sheet found lists no hazard statements and says the material may cause irritation. Treat the powder as an irritant and keep dust down.",
        "points": [
          {
            "label": "Classification",
            "line": "The supplier sheet prints no signal word and no hazard statements. PubChem's record for the compound has no GHS classification section."
          },
          {
            "label": "Toxicity",
            "line": "The sheet gives a median lethal dose of 4000 mg/kg for rat by mouth, and says the powder may cause irritation to eyes, skin, the stomach and the airways."
          },
          {
            "label": "Dust",
            "line": "Avoid raising dust. The sheet gives a threshold limit value of 1 mg/m3 as Fe (long-term value) and recommends a dust respirator, rubber gloves and safety glasses."
          },
          {
            "label": "In a fire",
            "line": "The sheet calls the material non-flammable and says decomposition gives metal oxide fume."
          }
        ],
        "level": 1,
        "verdict": "Irritant per the SDS; no GHS classification found"
      },
      {
        "title": "Chemical reactions",
        "lead": "The sheet lists oxidizing agents as reactive partners.",
        "points": [
          {
            "label": "Keep apart",
            "line": "Store apart from oxidizing agents, under dry inert gas, as the supplier's storage and reactivity sections advise."
          }
        ]
      }
    ]
  },
  "updated": "2026-11-01",
  "review": {
    "status": "draft",
    "method": "assistant",
    "checked_values": 15,
    "unreachable": 0,
    "caveats": 2,
    "note": "Values read in this run from the sources listed. The lattice and Neel and Curie values differ slightly between sources, so each is recorded with its own source and cell setting."
  },
  "sources": {
    "pmc-bfo-review": {
      "title": "Structure, Performance, and Application of BiFeO3 Nanomaterials",
      "id": "Nano-Micro Lett. 2020 Mar 28;12:81 (PMC7770668)",
      "url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC7770668/",
      "year": 2020,
      "kind": "paper",
      "license": "open access on PMC; licence not checked"
    },
    "samaterials-bfo": {
      "title": "Bismuth ferrite (BiFeO3) powder, catalogue BI6032, Stanford Advanced Materials product page",
      "id": "catalogue BI6032; CAS 12010-42-3",
      "url": "https://powder.samaterials.com/bi6032-bismuth-ferrite-powder.html",
      "kind": "datasheet",
      "license": "supplier web page, cited not reproduced"
    },
    "alfa-bfo": {
      "title": "Bismuth Ferrite, CAS 12010-42-3, Alfa Chemistry nanomaterials product page",
      "id": "catalogue ACM12010423; CAS 12010-42-3",
      "url": "https://nanomaterials.alfa-chemistry.com/product/bismuth-ferrite-cas-12010-42-3-306117.html",
      "kind": "web",
      "license": "supplier web page, cited not reproduced"
    },
    "samaterials-sds": {
      "title": "Safety Data Sheet: Bismuth Iron Oxide (Stanford Advanced Materials, catalogue BI6032), last revised 07/08/2015",
      "id": "catalogue BI6032",
      "url": "https://www.samaterials.com/tds/sc/1752820091-BI6032.pdf",
      "year": 2015,
      "kind": "datasheet",
      "license": "supplier document, cited not reproduced"
    },
    "pubchem-bfo": {
      "title": "PubChem compound record, Bismuth ferrite (CID 161118030), PUG-View JSON",
      "id": "CID 161118030",
      "url": "https://pubchem.ncbi.nlm.nih.gov/rest/pug_view/data/compound/161118030/JSON",
      "year": 2025,
      "kind": "database",
      "license": "public domain (NCBI)"
    },
    "arxiv-2201.11161": {
      "title": "Co-substituted BiFeO3: electronic, ferroelectric, and thermodynamic properties from first principles",
      "id": "arXiv:2201.11161",
      "url": "https://arxiv.org/pdf/2201.11161",
      "year": 2022,
      "kind": "paper",
      "license": "arXiv preprint, licence not checked"
    },
    "usgs-mcs2026-bismuth": {
      "title": "Mineral Commodity Summaries 2026: Bismuth",
      "id": "USGS MCS 2026, February 2026",
      "url": "https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-bismuth.pdf",
      "year": 2026,
      "kind": "report",
      "license": "public domain (USGS)"
    },
    "usgs-crit2025": {
      "title": "About the 2025 List of Critical Minerals (USGS)",
      "id": "Final 2025 List of Critical Minerals, November 2025",
      "url": "https://www.usgs.gov/programs/mineral-resources-program/science/about-2025-list-critical-minerals",
      "year": 2025,
      "kind": "web",
      "license": "public domain (USGS)"
    },
    "wikipedia-bfo": {
      "title": "Bismuth ferrite, Wikipedia (used for the CAS number, the abbreviation and the note on Neel and Curie temperatures only)",
      "url": "https://en.wikipedia.org/wiki/Bismuth_ferrite",
      "kind": "web",
      "license": "Wikipedia text, CC BY-SA (licence not re-checked in this run)"
    }
  },
  "license": "CC-BY-4.0",
  "url": "https://spacemushroom.com/profiles/bismuth-ferrite/"
}