spore: profile
id: lead-selenide
spore_version: 0.2
family: lead-chalcogenides
name: Lead selenide (PbSe)
abbreviation: PbSe
role: Narrow-gap semiconductor for infrared photodetectors, thermoelectric research and nanocrystal solar cells
category: semiconductors
type: gaas
summary: |
  Lead selenide (PbSe) is a grey, cubic compound of lead and selenium with a density of 8.1 g/cm3 at 20 °C, printed in its supplier safety data sheet. It is a narrow-gap semiconductor with a band gap of 0.27 eV at room temperature, per a 2022 Nanomaterials paper, and Wikipedia says it detects infrared radiation from 1.5 to 5.2 μm. Its supplier safety data sheet classes it as fatal if swallowed or inhaled (H300+H330), so the material is used in research and in infrared detector manufacture under strict handling.
best_for: Research-grade mid-infrared photodetector films and thermal-imaging detectors that need a detection range of 1.5 to 5.2 μm (Wikipedia)
weakest_at: 'Toxicity: the supplier safety data sheet classes lead selenide as fatal if swallowed or inhaled (H300+H330) and as a reproductive toxin (H360)'
identity:
  formula: PbSe
  cas: 12069-00-0
  crystal_system: cubic, halite (rock-salt) structure, cF8 (Wikipedia)
  space_group: Fm3m (No. 225)
  source: wiki-pbse
  where: Infobox, Structure (Halite (cubic), cF8; Fm3m, No. 225) and Identifiers (CAS 12069-00-0)
tags:
  environments: []
  stresses: []
  applications:
    - optics-and-cameras
    - electronics-and-chips
    - solar-arrays
properties:
  - benchmark: density
    label: Density (supplier safety data sheet)
    value: 8.1
    unit: g/cm3
    scope: material
    conditions:
      temperature: 20 °C (68 °F)
    method: Printed as Density at 20 °C (68 °F) in Section 9 of the Stanford Advanced Materials safety data sheet (revised 19/01/2023)
    status: ground
    source: sds-pbse
    where: Section 9, Density at 20 °C row
  - benchmark: density
    label: Density (product page)
    value: 8.1
    unit: g/cm3
    scope: material
    conditions:
      temperature: not stated on the page
    method: Printed as 8.10g/cm3 in the product summary table and Specification section of the Stanford Advanced Materials product page
    status: ground
    source: samaterials-pbse
    where: Product summary table; Specification section
  - benchmark: density
    label: Density (ChemBK)
    value: 8.1
    unit: g/mL
    scope: material
    conditions:
      temperature: 25 °C
      note: printed as lit. (literature value)
    method: Printed as 8.1 g/mL at 25 °C (lit.) in the Physico-chemical Properties section of ChemBK
    status: ground
    source: chembk-pbse
    where: Physico-chemical Properties, Density row
  - benchmark: melting_point
    label: Melting point (safety data sheet)
    value: 1065
    unit: °C
    scope: material
    conditions:
      basis: printed as 1065 °C (1949 °F); no test method given
    method: Printed in Section 9 of the safety data sheet as Melting point/Melting range
    status: ground
    source: sds-pbse
    where: Section 9, Melting point/Melting range row
  - benchmark: melting_point
    label: Melting point (Wikipedia)
    value: 1078
    unit: °C
    scope: material
    conditions:
      basis: infobox value, printed as 1,078 °C (1,972 °F; 1,351 K)
    method: Printed in the Wikipedia infobox, Properties section, as 1,078 °C
    status: ground
    note: Printed with a thousands comma. The infobox carries a verification marker, and it disagrees with the 1065 °C safety data sheet value.
    source: wiki-pbse
    where: Infobox, Properties (Melting point)
  - benchmark: melting_point
    label: Melting point (ChemBK)
    value: 1088
    unit: °C
    scope: material
    conditions:
      basis: printed as 1088°C with no test condition
    method: Printed in the Physico-chemical Properties section of ChemBK as Melting Point
    status: ground
    note: ChemBK prints the molecular formula as HPbSe, which is an error. The melting point is kept as printed and differs from the other two sources.
    source: chembk-pbse
    where: Physico-chemical Properties, Melting Point row
  - benchmark: molar_mass
    label: Molar mass
    value: 286.16
    unit: g/mol
    scope: material
    conditions:
      basis: as printed in the infobox
    method: Printed in the Wikipedia infobox, Properties section, as 286.16 g/mol; follows from the formula
    status: calculated
    source: wiki-pbse
    where: Infobox, Properties (Molar mass)
  - benchmark: band_gap
    label: Band gap at room temperature
    value: 0.27
    unit: eV
    scope: material
    conditions:
      temperature: room temperature, as printed
    method: Printed in Section 1 (Introduction) as a narrow bandgap of 0.27 eV at room temperature
    status: ground
    source: pmc-pbse-photodetector
    where: Section 1 (Introduction)
  - benchmark: band_gap
    label: Band gap with spin-orbit coupling (abstract)
    value: 0.16
    unit: eV
    scope: material
    conditions:
      basis: considering spin-orbit coupling, as printed in the abstract
    method: Printed in the abstract of a combined experimental and computational study on PbSe transport
    status: ground
    note: The abstract does not say whether this value is measured or computed.
    source: arxiv-pbse-transport
    where: Abstract
  - benchmark: band_gap
    label: Band gap without spin-orbit coupling (abstract)
    value: 0.27
    unit: eV
    scope: material
    conditions:
      basis: without spin-orbit coupling, as printed in the abstract
    method: Printed in the abstract of the same study as 0.27 eV without SOC
    status: ground
    note: The abstract does not say whether this value is measured or computed.
    source: arxiv-pbse-transport
    where: Abstract
  - benchmark: lattice_constant
    label: Lattice constant, cubic cell
    value: 6.12
    unit: Angstroms
    scope: material
    conditions:
      structure: cubic halite (rock-salt), space group Fm3m, as printed
    method: Printed in the Wikipedia infobox, Structure section, as 6.12 Angstroms
    status: ground
    source: wiki-pbse
    where: Infobox, Structure (Lattice constant)
  - benchmark: responsivity
    label: Responsivity at 2250 nm (iodine-sensitized film)
    value: 0.237
    unit: A/W
    scope: cell
    conditions:
      wavelength: 2250 nm
      bias: not printed for this sentence
      device: iodine-sensitized PbSe film made by chemical bath deposition
    method: Printed in Section 3.2 as responsive at 2250 nm with a responsivity of 0.237 A/W
    status: ground
    source: pmc-pbse-photodetector
    where: Section 3.2
  - benchmark: responsivity
    label: Responsivity at 808 nm (iodine-sensitized film)
    value: 30.27
    unit: A/W
    scope: cell
    conditions:
      wavelength: 808 nm
      bias: 1 V
      incident_power_density: 233 µW/cm²
    method: Printed in the Abstract as responsiveness of 30.27 A/W at 808 nm, at 1 V and 233 µW/cm²
    status: ground
    source: pmc-pbse-photodetector
    where: Abstract
  - benchmark: detection_range
    label: Detection range of the iodine-sensitized photodetector
    value: 2250
    value_high: 5000
    bound: range
    unit: nm
    scope: cell
    conditions:
      device: PbSe film photodetector with iodine sensitization
      temperature: not printed
    method: Printed in the Introduction as a device that detects over 2250 nm to 5000 nm
    status: ground
    source: pmc-pbse-photodetector
    where: Introduction
  - benchmark: seebeck_coefficient
    label: Seebeck coefficient at 300 K
    value: 198
    unit: μV K−1
    scope: material
    conditions:
      temperature: 300 K
      doping: not stated in the abstract
    method: Printed in the abstract as ~ 198 μV K−1 at 300 K
    status: ground
    note: The abstract does not say whether this value is measured or computed.
    source: arxiv-pbse-transport
    where: Abstract
  - benchmark: seebeck_coefficient
    label: Seebeck coefficient at 500 K
    value: 266
    unit: μV K−1
    scope: material
    conditions:
      temperature: 500 K
      doping: not stated in the abstract
    method: Printed in the abstract as 266 μV K−1 at 500 K
    status: ground
    note: The abstract does not say whether this value is measured or computed.
    source: arxiv-pbse-transport
    where: Abstract
  - benchmark: thermal_conductivity
    label: Thermal conductivity at 300 K
    value: 0.74
    unit: W m−1 K−1
    scope: material
    conditions:
      temperature: 300 K
      doping: not stated in the abstract
    method: Printed in the abstract as 0.74 (1.07) W m−1 K−1 at 300 (500) K
    status: ground
    note: The abstract does not say whether this value is measured or computed.
    source: arxiv-pbse-transport
    where: Abstract
  - benchmark: thermal_conductivity
    label: Thermal conductivity at 500 K
    value: 1.07
    unit: W m−1 K−1
    scope: material
    conditions:
      temperature: 500 K
      doping: not stated in the abstract
    method: Printed in the abstract as 0.74 (1.07) W m−1 K−1 at 300 (500) K
    status: ground
    note: The abstract does not say whether this value is measured or computed.
    source: arxiv-pbse-transport
    where: Abstract
  - benchmark: detection_range
    label: Infrared detection range (Wikipedia)
    value: 1.5
    value_high: 5.2
    bound: range
    unit: μm
    scope: material
    conditions:
      basis: wavelengths as printed; detector type and temperature not stated
    method: Printed in the Wikipedia Infrared detection section as it can detect IR radiation of wavelengths from 1.5 to 5.2 μm
    status: ground
    source: wiki-pbse
    where: Infrared detection section
corrosion:
  - environment: Water
    headline: Lead selenide is insoluble in water.
    effect: ChemBK and the safety data sheet both describe it as insoluble in water. Neither gives a solubility figure.
    rating: low
    conditions:
      temperature: not stated
    source: chembk-pbse
    where: Physico-chemical Properties, Water Solubility row
  - environment: Oxygen during heat treatment of PbSe films
    headline: Heating PbSe in air or oxygen forms oxidised products, which the authors detected by Raman spectroscopy at 400 °C.
    effect: After annealing at 400 °C, the Raman spectrum of the PbSe layer kept the PbSe bands near 100 cm−1, 125 cm−1 and 230 cm−1 and showed one more peak at 790 cm−1. The authors presume the 790 cm−1 peak comes from the PbSeO4 phase, not from PbSe.
    rating: moderate
    conditions:
      temperature: 400 °C annealing
      method: Raman spectroscopy, 532 nm excitation, as printed in the paper
    source: pmc-pbse-oxidation
    where: Section 3.3, Figure 6b
  - environment: Air and humidity at room temperature
    headline: No ageing or long-term air or humidity test for PbSe was found in the sources read.
    effect: The 2022 iodine-sensitization study reports no ageing, long-term air-exposure or stability test. It describes PbSe as having excellent chemical stability, but it gives no test result for that claim.
    rating: unknown
    conditions:
      basis: no ageing data reported
    source: pmc-pbse-photodetector
    where: Introduction and Section 3.2
  - environment: Acid, when heated
    headline: Heating PbSe while it is exposed to acid releases highly toxic hydrogen selenide gas.
    effect: ChemBK's flammability entry states that when heated and exposed to acid, lead selenide gives off highly toxic hydrogen selenide gas. The safety data sheet lists hydrogen selenide among its hazardous decomposition products.
    rating: moderate
    conditions:
      basis: heated and exposed to acid, as printed; acid strength not stated
    source: chembk-pbse
    where: Flammability Hazard Characteristics row
risks:
  hazards:
    - text: 'Supplier safety data sheet, classification under Regulation (EC) No 1272/2008 with signal word Danger: H300+H330 Fatal if swallowed or if inhaled; H360 May damage fertility or the unborn child; H373 May cause damage to organs through prolonged or repeated exposure.'
      ghs:
        - H300
        - H330
        - H360
        - H373
      source: sds-pbse
      where: Section 2, Classification and Label elements
    - text: 'PubChem GHS aggregate for lead selenide (CID 61550): H301 (100%) Toxic if swallowed; H331 (90.7%) Toxic if inhaled; H360 (97.7%) May damage fertility or the unborn child; H373 (100%) May cause damage to organs; H400 (100%) and H410 (100%) Very toxic to aquatic life.'
      ghs:
        - H301
        - H302
        - H331
        - H332
        - H360
        - H373
        - H400
        - H410
      source: pubchem-pbse
      where: GHS Classification section, GHS Hazard Statements
    - text: 'Wikipedia infobox, Hazards: H301, H302, H331, H332, H360, H373 and H410 with signal word Danger. Its hazard list differs from the safety data sheet, so both lists are kept.'
      ghs:
        - H301
        - H302
        - H331
        - H332
        - H360
        - H373
        - H410
      source: wiki-pbse
      where: Infobox, Hazards
  failure_risks:
    - mode: Release of hydrogen selenide gas
      trigger: Heating the solid while it is exposed to acid, or a fire involving the material
      consequence: Highly toxic hydrogen selenide gas is released, and the safety data sheet lists toxic metal compounds among the decomposition products.
      severity: high
      source: chembk-pbse
      where: Flammability Hazard Characteristics row; safety data sheet Section 10, Hazardous decomposition products
  side_effects:
    - text: In a fire the material can release toxic metal compounds and hydrogen selenide, so fire crews need a self-contained respirator (safety data sheet Section 5).
      affects: People near a fire or spill
      source: sds-pbse
      where: Section 5, Special hazards and Advice for firefighters; Section 10
  handling:
    - text: Keep the container tightly sealed and store it in a cool, dry place, as the safety data sheet requires.
      source: sds-pbse
      where: Section 7, Handling and Storage
    - text: Precautionary statement P260 says do not breathe dust, fume, gas, mist, vapours or spray; P284 calls for respiratory protection when ventilation is inadequate.
      source: sds-pbse
      where: Section 2, Precautionary statements
    - text: Section 8 lists a PEL (USA) long-term value of 0.2 mg/m3 as Se for lead(II) selenide (CAS 12069-00-0).
      source: sds-pbse
      where: Section 8, Exposure limits
  mitigations:
    - text: For fire, use a special powder for metal fires and do not use water (safety data sheet Section 5).
      source: sds-pbse
      where: Section 5, Suitable extinguishing agents
uses:
  - application: optics-and-cameras
    device: Mid-infrared photodetector film (research)
    example: An iodine-sensitized PbSe film detects over 2250 nm to 5000 nm and gives a responsivity of 0.237 A/W at 2250 nm (2022 Nanomaterials study).
    source: pmc-pbse-photodetector
    where: Abstract; Introduction; Section 3.2
  - application: optics-and-cameras
    device: Infrared detectors for thermal imaging
    example: Wikipedia says lead selenide is used to manufacture infrared detectors for thermal imaging, and that it can detect infrared radiation of wavelengths from 1.5 to 5.2 μm.
    source: wiki-pbse
    where: Lead section (intro); Infrared detection section
  - application: solar-arrays
    device: Lead selenide nanocrystals in nanocrystal solar cells
    example: Wikipedia names lead selenide nanocrystals, used as quantum dots, as an example in nanocrystal solar cells.
    source: wiki-pbse
    where: PbSe Quantum dots based photodetectors section
supply:
  - subject: Lead
    producers:
      - country: China
        share_percent: 42.2
        year: 2025
      - country: Australia
        share_percent: 10.7
        year: 2025
      - country: Peru
        share_percent: 6.4
        year: 2025
      - country: Russia
        share_percent: 5.8
        year: 2025
      - country: Mexico
        share_percent: 4.4
        year: 2025
    critical_lists:
      - list: USGS 2025 Final List of Critical Minerals (lead added in 2025)
        listed: true
    recycling: 'USGS: an estimated 1 million tons of secondary lead was produced in 2025, equivalent to 70% of apparent domestic consumption, nearly all recovered from old scrap, mostly lead-acid batteries.'
    substitutes:
      - USGS names substitutes for lead in cable covering, cans, solder for potable water and wheel weights. It gives no substitute for lead in PbSe.
    source: usgs-lead
    where: World Mine Production and Reserves table, 2025e (shares calculated by Space Mushroom against the world total (rounded) of 4,500 thousand t; the China and Australia values are printed in the table as 1,900 and 480); Recycling; Substitutes; Events, Trends and Issues (critical list)
  - subject: Selenium
    producers:
      - country: China
        share_percent: 53
        year: 2025
      - country: Japan
        share_percent: 16.8
        year: 2025
      - country: Russia
        share_percent: 8.4
        year: 2025
    critical_lists: []
    recycling: 'USGS: recycling of selenium is insignificant. Most scrap from electronic materials was exported for recovery of contained selenium.'
    substitutes:
      - 'USGS: amorphous silicon and cadmium telluride are the principal competitors with CIGS in thin-film photovoltaic cells. No substitute is named for PbSe.'
    source: usgs-selenium
    where: Events, Trends and Issues (China 53% of estimated global production); World Refinery Production table, 2025 (Japan 640 and Russia 320 against a world total (rounded) of 3,800 metric tons; shares calculated by Space Mushroom); Recycling; Substitutes
media: []
documents:
  - title: 'Lead Selenide: Safety Data Sheet (Stanford Advanced Materials, CAS 12069-00-0), revised 19/01/2023'
    type: sds
    url: https://samaterials.com/tds/1697120005-849-lead-selenide-evaporation-materials-sds.pdf
    year: 2023
  - title: 'Lead selenide powder, product PB6287: product summary and specifications (Stanford Advanced Materials)'
    type: datasheet
    url: https://www.samaterials.com/pb6287-lead-selenide-powder-pbse.html
  - title: 'PubChem: Lead selenide (CID 61550), GHS classification'
    type: database
    url: https://pubchem.ncbi.nlm.nih.gov/rest/pug_view/data/compound/61550/JSON
    year: 2025
  - title: Promoted Mid-Infrared Photodetection of PbSe Film by Iodine Sensitization Based on Chemical Bath Deposition (open access)
    type: paper
    url: https://pmc.ncbi.nlm.nih.gov/articles/PMC9105836/
    year: 2022
  - title: Thermodynamic Analysis and Experimental Study on the Oxidation of PbX (X = S, Se) Nanostructured Layers (open access)
    type: paper
    url: https://pmc.ncbi.nlm.nih.gov/articles/PMC9412640/
    year: 2022
  - title: 'Understanding the transport behaviour of PbSe: A combined experimental and computational study (arXiv abstract)'
    type: paper
    url: https://arxiv.org/abs/2408.03786
    year: 2024
  - title: 'USGS Mineral Commodity Summaries 2026: Lead'
    type: report
    url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-lead.pdf
    year: 2026
  - title: 'USGS Mineral Commodity Summaries 2026: Selenium'
    type: report
    url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-selenium.pdf
    year: 2026
gaps:
  - No refractive index, transmission range, dielectric constant or hardness value for PbSe was found in the sources read.
  - 'The melting point differs by source: 1065 °C (safety data sheet), 1078 °C (Wikipedia) and 1088 °C (ChemBK). All three are kept with their sources and none is preferred.'
  - No UNS, EN, DIN, JIS or trade-name designation for lead selenide was printed in any source read. The supplier catalogue number PB6287 is not a designation and is not listed.
  - No figure of merit (zT) for PbSe was printed in the abstract read, so no thermoelectric zT is recorded.
  - Detectivity (D*) is not printed in the 2022 photodetector paper, and the operating temperature of that device is not printed either.
  - No space, vacuum, radiation, atomic-oxygen, thermal-cycling or flight result for PbSe was found in any source read.
  - No quantitative solubility value was found; ChemBK and the safety data sheet say only insoluble in water.
  - The hazard statements disagree between the safety data sheet (H300+H330, H360, H373), PubChem (H301, H302, H331, H332, H360, H373, H400, H410) and Wikipedia (H301, H302, H331, H332, H360, H373, H410). All three lists are kept.
  - The arXiv abstract gives Seebeck coefficient and thermal conductivity values but does not say whether they are measured or computed, and it does not state the doping level.
  - Lead's status on the EU critical raw materials list and selenium's status on the USGS critical minerals list were not checked in this run.
  - No long-term air or humidity ageing data for PbSe was found.
  - Wikipedia gives PbSe a thermoelectric role and a 1.5 to 5.2 μm detection range, but gives no device or test condition for either.
  - 'Property names not in spores/property-canon.yaml and used as snake_case here: band_gap, molar_mass, lattice_constant, responsivity, detection_range, seebeck_coefficient. Canonical names were used for density, melting_point and thermal_conductivity.'
sources:
  samaterials-pbse:
    title: Lead selenide powder (PB6287) product page, Stanford Advanced Materials
    id: Catalog No. PB6287; CAS 12069-00-0
    url: https://www.samaterials.com/pb6287-lead-selenide-powder-pbse.html
    year: 2026
    kind: datasheet
    license: supplier page, cited not reproduced
  chembk-pbse:
    title: Lead selenide, ChemBK chemical database entry
    id: CAS 12069-00-0; EINECS 235-109-4
    url: https://www.chembk.com/en/chem/Lead%20selenide
    year: 2026
    kind: web
    license: cited, not reproduced
  wiki-pbse:
    title: Lead(II) selenide, Wikipedia article (infobox, structure, uses, hazards)
    id: Wikipedia, read 2026-11-01
    url: https://en.wikipedia.org/wiki/Lead_selenide
    year: 2026
    kind: web
    license: CC BY-SA 4.0 (Wikipedia)
  pubchem-pbse:
    title: PubChem compound record, Lead selenide (CID 61550), GHS Classification and Molecular Formula sections
    id: CID 61550; CAS 12069-00-0
    url: https://pubchem.ncbi.nlm.nih.gov/rest/pug_view/data/compound/61550/JSON
    year: 2025
    kind: database
    license: public domain (NCBI)
  sds-pbse:
    title: 'Safety Data Sheet: Lead Selenide (Stanford Advanced Materials, CAS 12069-00-0)'
    id: revised 19/01/2023; accessed 25/08/2023
    url: https://samaterials.com/tds/1697120005-849-lead-selenide-evaporation-materials-sds.pdf
    year: 2023
    kind: datasheet
    license: supplier document, linked not reproduced
  pmc-pbse-photodetector:
    title: Promoted Mid-Infrared Photodetection of PbSe Film by Iodine Sensitization Based on Chemical Bath Deposition
    id: Nanomaterials (Basel) 2022, 12(9), 1391; PMC9105836
    url: https://pmc.ncbi.nlm.nih.gov/articles/PMC9105836/
    year: 2022
    kind: paper
    license: open access (PubMed Central)
  pmc-pbse-oxidation:
    title: Thermodynamic Analysis and Experimental Study on the Oxidation of PbX (X = S, Se) Nanostructured Layers
    id: Micromachines, 2022 Jul 29; PMC9412640
    url: https://pmc.ncbi.nlm.nih.gov/articles/PMC9412640/
    year: 2022
    kind: paper
    license: open access (PubMed Central)
  arxiv-pbse-transport:
    title: 'Understanding the transport behaviour of PbSe: A combined experimental and computational study (arXiv abstract)'
    id: arXiv:2408.03786 (v2)
    url: https://arxiv.org/abs/2408.03786
    year: 2024
    kind: paper
    license: arXiv (abstract cited)
  nist-pb:
    title: 'NIST Atomic Weights and Isotopic Compositions for All Elements: lead (Pb, atomic number 82)'
    id: NIST Physical Measurement Laboratory, Standard Atomic Weight
    url: https://physics.nist.gov/cgi-bin/Compositions/stand_alone.pl?ele=Pb&all=all
    year: 2026
    kind: database
    license: public domain (NIST)
  nist-se:
    title: 'NIST Atomic Weights and Isotopic Compositions for All Elements: selenium (Se, atomic number 34)'
    id: NIST Physical Measurement Laboratory, Standard Atomic Weight
    url: https://physics.nist.gov/cgi-bin/Compositions/stand_alone.pl?ele=Se&all=all
    year: 2026
    kind: database
    license: public domain (NIST)
  usgs-lead:
    title: 'Mineral Commodity Summaries 2026: Lead'
    id: USGS MCS 2026, February 2026
    url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-lead.pdf
    year: 2026
    kind: report
    license: public domain (USGS)
  usgs-selenium:
    title: 'Mineral Commodity Summaries 2026: Selenium'
    id: USGS MCS 2026, February 2026
    url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-selenium.pdf
    year: 2026
    kind: report
    license: public domain (USGS)
license: CC-BY-4.0
updated: '2026-11-01'
review:
  status: draft
  method: assistant
  checked_values: 18
  unreachable: 1
  caveats: 2
  note: Read by an AI assistant on 2026-11-01. PubChem HTML page blocked by a browser check, so the PubChem JSON record was read instead. The arXiv PDF URL returned 404, so the arXiv abstract page was read instead. The ACAL detector page was not opened.
story:
  recipe:
    line: 'Lead selenide is PbSe: one lead atom bonded to one selenium atom, forming a cubic halite (rock-salt) lattice. The sources read here do not describe a synthesis route, so no process is given.'
    parts:
      - name: Lead
        symbol: Pb
        atoms: 1
        atomic_weight: 207.2
        role: The metal cation of the rock-salt lattice. Its heavy atomic mass dominates the compound's 8.1 g/cm3 density.
      - name: Selenium
        symbol: Se
        atoms: 1
        atomic_weight: 78.971
        role: The anion of the lattice. Selenium is a chalcogen, the same group as sulphur and tellurium.
  risk_groups:
    - title: For people
      level: 0
      verdict: Classed as fatal if swallowed or inhaled
      lead: The supplier safety data sheet classes lead selenide as Acute Tox. 2 with H300+H330, Fatal if swallowed or if inhaled, and adds H360 and H373.
      points:
        - label: The powder
          line: The safety data sheet prints H300+H330 Fatal if swallowed or if inhaled, H360 May damage fertility or the unborn child, and H373. PubChem's aggregate record lists H301 at 100% and H331 at 90.7% of reports.
        - label: Dust and fume
          line: The safety data sheet says not to breathe dust, fume, gas, mist, vapours or spray (P260), and calls for respiratory protection when ventilation is inadequate (P284).
        - label: In a fire
          line: Toxic metal compounds and hydrogen selenide can be released. The safety data sheet calls for a self-contained respirator and a special powder for metal fires, and says do not use water.
    - title: If heated with acid
      lead: The hazard here is a gas, not a cell failure. These statements come from the chemical database and the safety data sheet, not from field incidents.
      points:
        - label: Hydrogen selenide
          line: ChemBK states that when heated and exposed to acid, lead selenide gives off highly toxic hydrogen selenide gas.
        - label: Hazard disagreement
          line: The safety data sheet and Wikipedia list different hazard codes, and PubChem lists more of them. All three lists are kept in the record.
    - title: Handling and storage
      points:
        - label: Storage
          line: Keep the container tightly sealed and store it in a cool, dry place, as the safety data sheet requires.
        - label: Exposure
          line: The safety data sheet lists a PEL (USA) long-term value of 0.2 mg/m3 as Se for lead(II) selenide.
  why: 'Lead selenide (PbSe) is a narrow-gap semiconductor compound. It has a band gap of 0.27 eV at room temperature per a 2022 Nanomaterials paper, which places its response in the mid-infrared. Wikipedia says it is used to manufacture infrared detectors for thermal imaging and detects infrared radiation of wavelengths from 1.5 to 5.2 μm. Its main trade-off is toxicity: the supplier safety data sheet classes it as fatal if swallowed or inhaled. Its melting point is printed differently in three sources, 1065 °C, 1078 °C and 1088 °C, and all three are kept.'
  uses:
    - where: Mid-infrared photodetectors
      line: A 2022 study of iodine-sensitized PbSe films reports a responsivity of 0.237 A/W at 2250 nm. The same device detects over 2250 nm to 5000 nm, and the paper does not print the test temperature.
    - where: Infrared detectors for thermal imaging
      line: Wikipedia says lead selenide is used to manufacture infrared detectors for thermal imaging and opened the market for uncooled MWIR imaging cameras.
    - where: Nanocrystal solar cells
      line: Wikipedia names lead selenide nanocrystals, used as quantum dots, as an example in nanocrystal solar cells. It gives no efficiency figure.
  can_do:
    - label: Detect mid-infrared radiation
      line: an iodine-sensitized film responds at 2250 nm with a responsivity of 0.237 A/W, per the 2022 Nanomaterials paper.
    - label: Act as a thermoelectric material
      line: Wikipedia calls lead selenide a thermoelectric material, and the abstract read here gives a Seebeck coefficient of ~ 198 μV K−1 and a thermal conductivity of 0.74 W m−1 K−1, both at 300 K.
    - label: Band gap
      line: Respond to mid-infrared light because of its narrow band gap of 0.27 eV at room temperature, per the 2022 Nanomaterials paper.
  compare: The three melting points printed for lead selenide (1065 °C in the safety data sheet, 1078 °C in Wikipedia and 1088 °C in ChemBK) differ by more than the rounding in any one source, so the most reliable figure is not settled by these sources. The density is printed as 8.1 g/cm3 by the safety data sheet and as 8.10 g/cm3 by the supplier's product page. Both agree on the same value to the precision printed.
  compare_rows:
    - label: Density
      benchmark: density
    - label: Melting point
      benchmark: melting_point
    - label: Thermal conductivity
      benchmark: thermal_conductivity
  handling:
    - The safety data sheet classes the powder as fatal if swallowed or inhaled, so use it only with local exhaust and respiratory protection where ventilation is inadequate.
    - Keep the container tightly sealed in a cool, dry place.
    - Do not let it contact acid when hot, because it releases hydrogen selenide.
  good_for:
    - Mid-infrared photodetector research. A 2022 study measured a responsivity of 0.237 A/W at 2250 nm for an iodine-sensitized film.
    - Thermal-imaging detector manufacture. Wikipedia says lead selenide is used for these detectors and can detect 1.5 to 5.2 μm.
  watch_out:
    - Toxicity. The safety data sheet classes it as fatal if swallowed or inhaled, with H300+H330.
    - Conflicting melting points. The sources give 1065 °C, 1078 °C and 1088 °C.
    - No ageing or humidity data. No long-term air or humidity ageing test was found.
  verdict: Lead selenide is a useful narrow-gap infrared material, but the toxicity is significant, and the sources read here give no ageing, space or flight data.