LEAD DIOXIDE

Lead dioxide is a dark-brown to black, odourless, inorganic compound with chemical formula PbO₂, molecular weight 239.20 g/mol, CAS number 1309-60-0, EC number 215-174-5, density 9.38 g/cm³, melting point 290°C (decomposes), refractive index 2.30, and existing as two crystalline polymorphs — α-PbO₂ (orthorhombic, space group Pbcn, scrutinyite) and β-PbO₂ (tetragonal, space group P4₂/mnm, plattnerite) — in which lead is in the +4 oxidation state (Pb⁴⁺) and exhibits anomalous metallic conductivity (resistivity as low as 10⁻⁴ Ω·cm) due to non-stoichiometric oxygen deficiency (actual O/Pb ratio 1.90–1.98).
Lead dioxide is the most commercially important lead(IV) compound, serving as the positive plate (cathode) material in virtually all lead-acid storage batteries (automotive, industrial backup, and renewable energy storage) via the reversible comproportionation reaction Pb + PbO₂ + 2HSO₄⁻ + 2H⁺ ⇌ 2PbSO₄ + 2H₂O (E° = +2.05 V), and as an inexpensive anode material in industrial electrolysis reactions for the production of glyoxylic acid, potassium dichromate regeneration, and electroplating.
Lead dioxide is classified under GHS with Signal Word Danger and hazard statements H272 (may intensify fire; oxidiser), H302 (harmful if swallowed), H332 (harmful if inhaled), H360 (may damage fertility or the unborn child), H372/H373 (causes/may cause damage to organs — blood, CNS, PNS, kidneys — through prolonged or repeated exposure), and H410 (very toxic to aquatic life with long-lasting effects); it is classified as a suspected/probable human carcinogen by IARC (Group 2A for inorganic lead compounds), NTP (reasonably anticipated), and ACGIH (A3); occupational exposure limit: OSHA/ACGIH TLV 0.05 mg/m³ TWA; NIOHS IDLH 100 mg/m³.

CAS Number: 1309-60-0
EC Number: 215-174-5
Molecular Formula: PbO₂
Molecular Weight: 239.20 g/mol

Synonyms: Lead(IV) oxide, Lead peroxide, Lead superoxide, Plumbic oxide, Lead oxide (PbO₂), Plattnerite (β-PbO₂ mineral form), Scrutinyite (α-PbO₂ mineral form), Lead Brown, Lead Oxide Brown, dioxolead, dioxoplumbane, plumbanedione, Bioxyde de plomb, Peroxyde de plomb, CI 77580, C.I. 77580, CCRIS 6254, HSDB 4335, RTECS OG0700000, MFCD00011165, DTXSID5025497, SCCHEMBL2144, UN 1872, CAS 1309-60-0

Lead Dioxide has the chemical formula PbO₂ and contains lead in the +4 oxidation state.
With a molar mass of approximately 239.19 g/mol, Lead Dioxide belongs to the group of inorganic lead oxides.

Lead Dioxide normally appears as a dark-brown or nearly black crystalline powder.
Water dissolves very little Lead Dioxide under ordinary conditions.

Two principal crystalline forms of Lead Dioxide are known as alpha and beta.
The orthorhombic crystal structure distinguishes alpha-Lead Dioxide from the tetragonal beta form.

Alpha-Lead Dioxide generally forms a compact structure that promotes strong contact between particles.
A more porous structure and lower electrical resistance often characterize beta-Lead Dioxide.

The relatively good electrical conductivity of Lead Dioxide supports its use in electrochemical systems.
As a powerful oxidizing material, Lead Dioxide can accept electrons from many other substances.

Lead Dioxide serves as the positive active material in conventional lead-acid batteries.
During battery discharge, Lead Dioxide reacts with sulfuric acid and forms lead sulfate.

Charging a lead-acid battery converts lead sulfate back into Lead Dioxide on the positive plate.
The particle size and porosity of Lead Dioxide strongly influence battery capacity and service life.

A suitable balance between alpha- and beta-Lead Dioxide can improve the mechanical and electrochemical properties of battery plates.
Manufacturers carefully control Lead Dioxide morphology to obtain reliable charge and discharge performance.

Electrodeposition can produce adherent Lead Dioxide coatings on conductive surfaces.
Titanium, graphite and lead alloys may serve as substrates for Lead Dioxide electrodes.

Beta-Lead Dioxide is often preferred for anodes because of its conductivity and electrochemical activity.
An alpha-Lead Dioxide underlayer can improve the adhesion of a beta-Lead Dioxide coating.

Lead Dioxide electrodes promote the electrochemical oxidation of numerous organic compounds.
Wastewater-treatment studies frequently examine Lead Dioxide anodes for breaking down persistent pollutants.

A high oxygen-evolution overpotential allows Lead Dioxide to support strong oxidation reactions at an electrode surface.
Electrochemical ozone-generation systems can also employ specially prepared Lead Dioxide electrodes.

Organic electrosynthesis represents another field in which Lead Dioxide can function as an anode material.
Some electroplating processes use Lead Dioxide electrodes because they resist corrosion in acidic solutions.

The dye industry has used Lead Dioxide as an oxidizing agent in selected manufacturing processes.
Lead Dioxide can also participate in the curing of certain sulfur-containing polymers.

Chemical oxidation of lead(II) compounds provides one method for preparing Lead Dioxide.
Anodic deposition from a lead-containing electrolyte offers another common route to Lead Dioxide films.

Current density, temperature, acidity and additives can modify the crystal form of electrodeposited Lead Dioxide.
Doping Lead Dioxide may improve conductivity, durability or catalytic activity.

Spent lead-acid battery paste commonly contains Lead Dioxide together with lead sulfate and other lead compounds.
Recycling processes recover the lead content of Lead Dioxide for use in new materials and batteries.

Strong heating can cause Lead Dioxide to release oxygen and transform into lower lead oxides.
Reducing agents readily react with Lead Dioxide because of its pronounced oxidizing character.

Uses of Lead Dioxide:
Lead dioxide is the essential positive plate (cathode) material in lead-acid storage batteries, accumulating as PbO₂ on the positive plate during charging and being reduced back to PbSO₄ during discharge; lead-acid batteries using PbO₂ power virtually all passenger vehicles, motorcycles, forklifts, industrial uninterruptible power supplies (UPS), and grid-scale renewable energy storage systems.
Lead dioxide is used as an inexpensive anode material in various industrial electrolytic processes: regeneration of potassium dichromate (replacing more expensive platinum and graphite electrodes), oxygen anodes for electroplating copper and zinc in sulfate baths, oxidation of wastewater organic contaminants, and production of glyoxylic acid from oxalic acid in sulfuric acid electrolyte; β-PbO₂ is preferred for this purpose due to its lower resistivity, good corrosion resistance at low pH, and high overvoltage for oxygen evolution.
Lead dioxide is used as a powerful oxidising agent in the manufacture of dyes and intermediates (including discharge dyeing with indigo using PbO₂ as a mordant), in the manufacture of matches (combined with amorphous phosphorus as the ignition surface on the striking face), and in the production of pyrotechnics, explosives, and incendiary fuses where rapid oxygen release is required.
Lead dioxide is used as a curing agent (vulcanising agent) for polysulfide rubbers, liquid polysulfide polymers, low-molecular-weight butyl rubber, and polyisoprene; it acts as an oxidative crosslinker forming disulfide bridges between sulfide polymer chains.
Lead dioxide is used in high-voltage surge arrester (lightning arrester) assemblies as a resistor element providing voltage-dependent resistance, and in protective pipe coatings for lead service lines conveying chlorinated water, where PbO₂ forms a passivating layer that prevents lead leaching.
Lead dioxide is used as an analytical reagent in analytical chemistry (organic elemental analysis and chromatographic analysis), as an oxidising agent in the synthesis of chlorinated hydrocarbons, epoxides, and other specialty chemicals, and in the electrolytic determination of lead in glass matrices.
Lead dioxide was used historically until the 1970s as an adsorbent for sulfur dioxide monitoring in ambient air pollution surveillance; it also finds application in lead-based glass and ceramic formulations and in PbO₂-graphite composite electrodes for sensing ammonia, nitrite, and phenols.

Benefits and Advantages of Lead Dioxide:
The anomalous metallic conductivity of PbO₂ (resistivity ~10⁻⁴ Ω·cm) — which arises from the non-stoichiometric excess of lead in the lattice, creating free charge carriers — allows it to function as an electrode material with a well-defined electrode potential despite being an inorganic oxide, a property unique among common metal oxides.
Lead dioxide provides the highest cell voltage among common aqueous rechargeable battery chemistries (E° = +2.05 V for the Pb/PbO₂ cell in H₂SO₄) at extremely low cost per kilowatt-hour of stored energy, making lead-acid batteries with PbO₂ positive plates the dominant technology for automotive starting-lighting-ignition and industrial backup power globally.
As an electrolytic anode material, PbO₂ withstands highly corrosive media including dilute and concentrated sulfuric acid, nitric acid, and chloride solutions, providing service life competitive with platinum and graphite at a fraction of the cost; it can also withstand chlorine evolution in hydrochloric acid baths, making it versatile across strongly oxidising electrolyte environments.
The thermal decomposition of PbO₂ provides a controlled stepwise route to multiple lead oxide phases — Pb₁₂O₁₉ (290°C) → Pb₁₂O₁₇ (350°C) → Pb₃O₄ (375°C) → PbO (600°C) — making it a useful precursor for the synthesis of a range of lead oxide products by simply varying the decomposition temperature and atmosphere.

Features of Lead Dioxide:
Lead dioxide is a dark brown to black crystalline powder, odourless, density 9.38 g/cm³ (specific gravity 9.375 at 20°C), melting point 290°C (decomposes with oxygen evolution rather than melting), refractive index 2.30, vapour density 8.2; specific heat capacity Cp(crystal) = 0.27 J/(g·K) at 25°C; practically insoluble in water and alcohol; soluble in glacial acetic acid; moderately soluble in hydrochloric acid (with Cl₂ evolution); soluble in concentrated nitric acid in the presence of H₂O₂ or oxalic acid; soluble in hot caustic alkali (forming hydroxyplumbate); and slowly soluble in dilute nitric acid.
Lead dioxide exists in two crystalline polymorphs: α-PbO₂ (orthorhombic, space group Pbcn No. 60, Pearson symbol oP12, lattice constants a = 0.497 nm, b = 0.596 nm, c = 0.544 nm, Z = 4; Pb is six-coordinate; octahedra linked by adjacent edges to give zigzag chains) and β-PbO₂ (tetragonal, space group P4₂/mnm No. 136, rutile-type, lattice constants a = 0.491 nm, c = 0.3385 nm, Z = 2; octahedra share opposite edges to give columns joined by corner sharing); both polymorphs occur naturally as rare minerals scrutinyite (α) and plattnerite (β).
Lead dioxide is a non-combustible solid that strongly enhances the flammability and intensity of fires involving combustible materials by acting as an oxygen source; it decomposes at 290°C with release of O₂; at very high temperatures in fire conditions it produces irritating, corrosive, and toxic lead oxide fumes; its NFPA 704 rating is Health 4 / Fire 0 / Reactivity 3 / OX.
Key electrochemical parameter: The O/Pb ratio of PbO₂ varies between 1.90 and 1.98 depending on preparation method; this sub-stoichiometry creates excess Pb²⁺ ions and free electrons responsible for metallic conductivity; the resistivity of dense PbO₂ (electrolytic) is ~10⁻⁴ Ω·cm; porous battery material has higher resistivity; resistance increases with temperature by ~0.2%/°C at room temperature.

Chemical Properties of Lead Dioxide:
Lead dioxide has IUPAC name dioxolead (lead(IV) oxide), SMILES O=[Pb]=O (or [Pb](=O)=O), InChI=1S/2O.Pb, InChIKey YADSGOSSYOOKMP-UHFFFAOYSA-N; PubChem CID 14793; ChemSpider 14109; MDL MFCD00011165; EC 215-174-5; ECHA InfoCard 100.013.795; CompTox DTXSID5025497; RTECS OG0700000; UNII 7JJD3ICL6A.
Lead dioxide is amphoteric with prevalent acidic properties; it dissolves in strong bases to form the hydroxyplumbate ion: PbO₂ + 2NaOH + 2H₂O → Na₂[Pb(OH)₆]; it reacts with basic oxides in the melt to yield orthoplumbates M₄[PbO₄]; in hot acids, the unstable Pb⁴⁺ state converts to Pb²⁺ with oxygen liberation: 2PbO₂ + 2H₂SO₄ → 2PbSO₄ + 2H₂O + O₂; 2PbO₂ + 4HNO₃ → 2Pb(NO₃)₂ + 2H₂O + O₂; PbO₂ + 4HCl → PbCl₂ + 2H₂O + Cl₂.
Lead dioxide is a powerful oxidising agent capable of oxidising Mn²⁺ to MnO₄⁻ (permanganate): 2MnSO₄ + 5PbO₂ + 6HNO₃ → 2HMnO₄ + 2PbSO₄ + 3Pb(NO₃)₂ + 2H₂O; and Cr(III) to chromate: 2Cr(OH)₃ + 10KOH + 3PbO₂ → 2K₂CrO₄ + 3K₂PbO₂ + 8H₂O; it also oxidises iodide to iodine in alkali iodide solutions.
Lead dioxide undergoes a stepwise thermal decomposition in air: 24PbO₂ → 2Pb₁₂O₁₉ + 5O₂ (290°C); Pb₁₂O₁₉ → Pb₁₂O₁₇ + O₂ (350°C); 2Pb₁₂O₁₇ → 8Pb₃O₄ + O₂ (375°C); 2Pb₃O₄ → 6PbO + O₂ (600°C); Pb₂O₃ is obtainable at 580–620°C under 1,400 atm O₂ pressure; thermal decomposition of PbO₂ is the principal industrial route to multiple lead oxide phases.

Production of Lead Dioxide:
The principal industrial chemical route is oxidation of red lead (Pb₃O₄) in alkaline slurry in a chlorine atmosphere; alternative chemical routes include: reaction of lead(II) acetate with calcium hypochlorite (bleaching powder) — Pb(OH)₃⁻ + ClO⁻ → PbO₂ + Cl⁻ + OH⁻ + H₂O; reaction of Pb₃O₄ with nitric acid — Pb₃O₄ + 4HNO₃ → PbO₂ + 2Pb(NO₃)₂ + 2H₂O; and fusion of lead monoxide with sodium nitrate and sodium chlorate mixtures.
The principal electrochemical production route is anodic electrodeposition: in dilute sulfuric acid, PbO₂ deposits on pure lead or substrate electrodes (titanium, niobium, tantalum, or graphite) at an electrode potential of approximately +1.5 V vs. SHE; production conditions include galvanostatic current ~100 A/m², deposition time ~30 minutes, with lead nitrate in flowing dilute nitric acid; substrates are sand-blasted before deposition to improve adhesion; this method yields hard and brittle PbO₂ with Mohs hardness 5.5 when on hard substrates.
Lead dioxide is commercially available at ≥94% (LR), ≥97.0% (ACS reagent), ≥99.0% (pa grade), ≥99.995% (metals basis, Puratronic grade), and ≥99.998% (trace metals basis) purity levels as a dark brown to black powder; specification limits include: dilute HNO₃ insolubles ≤0.2%, Cl ≤0.002%, NO₃ ≤0.02%, SO₄ ≤0.05%, Ca ≤0.02%, Cu ≤0.05%, Fe ≤0.02%, Mn ≤0.0005%, K ≤0.05%, Na ≤0.1%.

Lead Dioxide Material Safety Data Sheet (MSDS):

Handling of Lead Dioxide:
Lead dioxide is a highly hazardous compound classified Danger under GHS; handling must be performed only by trained personnel in a fume hood or well-ventilated area; avoid breathing dust and fumes (P260, P261); do not eat, drink, or smoke when using (P270); obtain special instructions before use (P201, P202); avoid contact with combustible materials and reduce agents (P210, P220, P221).
Women of childbearing potential must avoid exposure (reproductive hazard H360); use only personal protective equipment specified in Section 8 (P280, P281); wash hands thoroughly after handling (P264); the material is regulated by OSHA Standard 1910.1025 (lead) — all requirements of the standard must be followed; contaminated work clothes must not be taken home.

Lead Dioxide SDS:

Stability and Reactivity of Lead Dioxide:

Chemical stability:
Lead dioxide is stable under recommended storage conditions in a cool, dry, well-ventilated area in tightly closed containers. Lead dioxide decomposes at 290°C with release of oxygen and toxic lead oxide fumes.

Reactivity:
Lead dioxide is a powerful oxidising agent; it reacts violently with many substances including reducing agents, combustible materials, reactive metals, and organic compounds.
Specific violent/hazardous reactions: reacts violently with H₂S; ignites with hydroxylamine; reacts violently with H₂O₂, phenylhydrazine, and sulfuryl chloride; reacts with incandescence with SO₂; explodes when ground with boron or yellow phosphorus; mixtures with sulfur and red phosphorus ignite; reacts vigorously on heating with alkaline earth sulfides (CaS, SrS, BaS).

Conditions to avoid:
Contact with combustible materials (wood, paper, oil, clothing) — may ignite them.
Contact with reducing agents — violent oxidation.
Elevated temperatures (≥290°C) — O₂ release and toxic fume generation.
Heat and contamination — risk of fire and explosion.
Contact with strong acids — oxygen evolution and Pb²⁺ formation.

Incompatible materials (reactions may be violent or explosive):
Reducing agents; reactive metals (Al, Mg, K, Na, Zn, metal powders).
Combustible materials (wood, paper, oil, clothing).
Strong acids (H₂SO₄, HNO₃, HCl).
Hydrogen sulfide, hydrogen peroxide, hydroxylamine, phenylhydrazine.
Sulfuryl chloride, chlorine trifluoride, phosphorus trichloride.
Sulfur, red/friction phosphorus, boron, silicon, tungsten, molybdenum.
Calcium sulfide, strontium sulfide, barium sulfide.
Amines, hydrides, carbides, metal sulfides, glycerin.
Cellulose-based and expanded polymeric absorbents (reactive with oxidiser).

Hazardous decomposition products:
Toxic lead oxide fumes and particulates (Pb, PbO, various lead oxides) upon heating.
Oxygen gas (O₂) — accelerates fire and explosion risk.
Chlorine gas (Cl₂) when reacting with HCl.
Sulfur dioxide (SO₂) from reactions with sulfur-containing materials.

Handling and Storage of Lead Dioxide:

Handling:
Handle only in a fume hood or well-ventilated area; avoid dust generation at all times.
Wear full PPE: chemical-resistant gloves, chemical splash goggles, face shield, chemical-resistant protective clothing.
Use type P3 (EN 143) respirator cartridges or equivalent P100 respirator.
Avoid all contact with combustible materials and reducing agents.
Do not eat, drink, or smoke in work areas; do not take contaminated clothing home.
Wash hands thoroughly after handling.

Storage:
Store in tightly closed containers in a cool, dry, well-ventilated area.
Separate from food, feed, flammables, combustibles, and all incompatible materials (especially reducing agents, reactive metals, peroxides, permanganates, chlorates, nitrates, and organic material).
Storage class: 5.1B — Oxidising hazardous materials.
Colour code: Yellow — Reactive Hazard.
Shelf life: Indefinite if stored properly.
Complies with OSHA Standard 1910.1025 (lead) and NFPA 43A (storage of oxidisers).
ERG Guide 140 (Oxidizers): Isolate spill or leak area ≥25 m for solids; consider downwind evacuation ≥100 m for large spills; isolate ≥800 m in all directions if tank car involved in fire.

First Aid Measures for Lead Dioxide:

Inhalation:
Immediately remove the affected person to fresh air; keep at rest in a position comfortable for breathing (P304+P340).
Immediately call a physician even if no symptoms (wheezing, coughing, shortness of breath) develop; provide SCBA for rescuers; monitoring for delayed lead toxicity effects is essential.

Skin contact:
Immediately flood affected skin with water while removing and isolating all contaminated clothing; gently wash all affected skin with soap and water.
If symptoms develop, immediately call a physician and transport to hospital.

Eye contact:
Remove contact lenses if present; immediately irrigate eyes with water or normal saline for 20–30 minutes.
Seek ophthalmological attention immediately even if no symptoms (redness, irritation) develop.

Ingestion:
Immediately call a hospital or poison control centre; give large quantities of water and, if advised by medical personnel, activated charcoal slurry or milk or beaten egg whites.
Do NOT induce vomiting if unconscious or convulsing; transport immediately to hospital.
Medical note: Lead poisoning antidote — CaEDTA chelation therapy (only under hospitalisation); BAL (British Anti-Lewisite, dimercaprol) has some value for severe cases; pre-medication with ephedrine sulfate reduces BAL toxicity; periodic medical examination recommended.

Firefighting Measures for Lead Dioxide:

Suitable extinguishing media:
Small fire: water only; do NOT use dry chemicals or foam.
Large fire: flood fire area with water from distance.

Specific hazards:
Lead dioxide is non-combustible but strongly accelerates burning of combustibles by releasing O₂; lead oxide fumes (PbO, Pb₂O₃) generated are highly toxic.
Containers may explode when heated; runoff from fire control water may cause environmental and explosion hazards.

Protective equipment for firefighters:
Positive pressure SCBA must be worn; chemical protective clothing specifically recommended by the manufacturer where there is NO fire risk; structural firefighter clothing provides only limited chemical protection.

Firefighting procedures:
Evacuate all non-essential personnel; fight fire from maximum safe distance or use unmanned master-stream devices.
Cool containers with flooding quantities of water; always stay away from containers in direct contact with flames.

Accidental Release Measures for Lead Dioxide:

Personal precautions:
Isolate spill area ≥25 m (solid spill); evacuate downwind ≥100 m for large spills; wear positive pressure SCBA and full chemical protective clothing.
Keep all combustibles away from spilled material; do NOT touch damaged containers or spilled material without full PPE.

Environmental precautions:
Do NOT let lead dioxide enter the environment (very toxic to aquatic life, H410); keep away from drains, sewers, and water courses.

Clean-up methods:
Small dry spill: with clean shovel, place into clean dry container; cover loosely; move from spill area.
Do not use cellulose-based or expanded polymeric absorbents (reactive with PbO₂).
Moisten first if appropriate to prevent dusting; carefully collect all remainder in sealed, labelled containers.
Waste disposal: convert to soluble salt, precipitate as sulfide; dispose as hazardous waste via licensed contractor to approved landfill; RCRA code D008; do not discharge to drains or sewers.

Exposure Controls / Personal Protective Equipment for Lead Dioxide:

Engineering controls:
Work only in a fume hood or with full local exhaust ventilation; enclose processes where possible.
Emergency eyewash stations and safety showers must be accessible.

Eye protection:
Chemical splash goggles and face shield — both required simultaneously.

Hand protection:
Chemical-resistant gloves (nitrile, neoprene, or equivalent tested to EN 374); inspect before use, dispose of contaminated gloves after use.

Skin and body protection:
Chemical-resistant full body protective suit; fully encapsulating suit for large spill response.

Respiratory protection:
Type P3 (EN 143) respirator for routine dust control; positive pressure SCBA for spills, high concentrations, or fire response.

Hygiene measures:
Do not eat, drink, or smoke in work areas; wash hands and exposed skin thoroughly after handling; do not take contaminated work clothing home; periodic medical examination recommended under OSHA 1910.1025.

Lead Dioxide Identifiers:
CAS Number: 1309-60-0
EC Number: 215-174-5
MDL Number: MFCD00011165
ECHA InfoCard: 100.013.795
PubChem CID: 14793
ChemSpider: 14109
RTECS: OG0700000
UNII: 7JJD3ICL6A
CompTox (EPA): DTXSID5025497
CBNumber: CB9196612
IUPAC Name: dioxolead (lead(IV) oxide)
Molecular Formula: PbO₂ (O₂Pb)
Molecular Weight: 239.20 g/mol
Exact Mass: 239.966481 Da
Monoisotopic Mass: 239.966481 Da
SMILES: O=[Pb]=O (or [Pb](=O)=O)
InChI: InChI=1S/2O.Pb
InChIKey: YADSGOSSYOOKMP-UHFFFAOYSA-N
HBD: 0; HBA: 2; Rotatable bonds: 0; Heavy atom count: 3; Complexity: 18.3; TPSA: 34.1 Ų
GHS Signal Word: Danger
GHS Hazard Statements: H272, H302, H332, H360, H372, H373, H410
GHS Precautionary Statements: P201, P202, P210, P220, P221, P260, P261, P264, P270, P271, P273, P280, P281, P301+P312, P304+P312, P304+P340, P308+P313, P312, P314, P330, P370+P378, P391, P405, P501
NFPA 704: Health 4 / Fire 0 / Reactivity 3 / OX
Risk Statements: R61, R8, R20/22, R33, R50/53, R62
Safety Statements: S53, S45, S60, S61
UN Number: UN 1872
Hazard Class: 5.1 (Oxidiser)
Packing Group: III
RIDADR: UN 1872
WGK Germany: 3
Storage Class: 5.1B
HS Code: 28249090
TSCA: Listed; EINECS: Listed; RCRA code: D008
REACH: Active registrations
ACGIH TLV: 0.05 mg/m³ TWA (as Pb); A3 — confirmed animal carcinogen
NIOHS TLV: 0.05 mg/m³ TWA; IDLH 100 mg/m³
EU-OEL (binding): 0.15 mg/m³ TWA
IARC: Group 2A (inorganic lead compounds)
NTP: Reasonably anticipated to be a human carcinogen
MAK: Carcinogen category 2; germ cell mutagen group 3A
Guinea pig i.p. LD50: 220 mg/kg (Venugopal, Luckey)
Hazard Classifications: Acute Tox. 4 Oral; Acute Tox. 4 Inhalation; Ox. Sol. 3; Repr. 1A; STOT RE 2; Aquatic Acute 1; Aquatic Chronic 1
Target organs: Blood, bone marrow, CNS, PNS, kidneys, immune system, reproductive system

Properties of Lead Dioxide:
Physical state: Solid
Appearance: Dark brown to black crystalline powder
Odour: Odourless
Molecular formula: PbO₂
Molecular weight: 239.20 g/mol
Melting point: 290°C (decomposes with O₂ evolution)
Density: 9.38 g/cm³ (specific gravity 9.375 at 20°C)
Refractive index: 2.30 (ω, Li lamp)
Specific heat capacity: 0.27 J/(g·K) at 25°C
Vapour density: 8.2 (air = 1)
Water solubility: Insoluble
Solubility in acetic acid: Slowly soluble
Solubility in HCl: Moderately soluble (Cl₂ evolution)
Solubility in hot NaOH: Soluble (hydroxyplumbate)
Flash point: Non-flammable
Oxidising properties: Category 2 oxidiser
Electrical resistivity (dense): ~10⁻⁴ Ω·cm (metallic)
Crystal system: α-PbO₂ orthorhombic (Pbcn); β-PbO₂ tetragonal (P4₂/mnm)
GHS Classification: Danger — H272, H302, H332, H360, H372, H373, H410
OEL (ACGIH/OSHA as Pb): 0.05 mg/m³ TWA

Lead Dioxide Properties — Specifications:
Product name: Lead dioxide (Lead(IV) oxide)
CAS Number: 1309-60-0
EC Number: 215-174-5
Molecular Formula: PbO₂
Molecular Weight: 239.20 g/mol
Purity grades: LR ≥94%; ACS reagent ≥97.0%; pa ≥99.0%; Puratronic ≥99.995%; trace metals basis ≥99.998%
Specification (ACS grade): Dilute HNO₃ insolubles ≤0.2%; Cl ≤0.002%; NO₃ ≤0.02%; SO₄ ≤0.05%; Ca ≤0.02%; Cu ≤0.05%; Fe ≤0.02%; Mn ≤0.0005%; K ≤0.05%; Na ≤0.1%
Appearance: Brown to black powder
Melting point: 290°C (decomposes)
Density: 9.38 g/cm³
Storage: Cool, dry, well-ventilated, away from combustibles and incompatibles; 5.1B storage class
Format: Powder; available as DryPowder or WetSolid
Documents: CoA (Certificate of Analysis), MSDS/SDS available

Names of Lead Dioxide:
Lead dioxide
Lead(IV) oxide
Lead peroxide
Lead superoxide
Plumbic oxide
Lead oxide (PbO₂)
Lead Brown
Lead Oxide Brown
dioxolead
dioxoplumbane
plumbanedione
Plattnerite (β-PbO₂)
Scrutinyite (α-PbO₂)
Bioxyde de plomb
Peroxyde de plomb
Bleisuperoxyd
CI 77580
C.I. 77580
CCRIS 6254
HSDB 4335
UNII-7JJD3ICL6A
UN1872
MFCD00011165
CAS 1309-60-0