What Is Lead(II) Iodide?
Lead(II) iodide, with the formula PbI2, is known for its CAS number 10101-63-0. Once used as a pigment, its use has declined due to toxicity concerns. It is considered harmful and is regulated under various laws.
Uses of Lead(II) Iodide
It serves in applications such as X-ray and gamma-ray detection, perovskite solar cells, and various industrial processes. Its ability to emit photoelectrons under ultraviolet light and its role in forming light-absorbing layers in solar cells are particularly noted, despite the toxicity of lead and the thermal sensitivity of associated materials.
Properties of Lead(II) Iodide
Lead(II) iodide appears as a light yellow to yellowish-red crystalline substance, with a melting point of 402°C and boiling point of 872°C. It’s non-flammable, soluble in potassium iodide solutions but insoluble in water and ethanol.
Types of Lead(II) Iodide
Available primarily for research, lead(II) iodide is sold in various quantities suitable for laboratory use. Its sensitivity to air and humidity often necessitates handling in an inert atmosphere, such as within a glove box.
Other Information on Lead(II) Iodide
1. Synthesis of Lead(II) Iodide
Produced by reacting hydroiodic acid or potassium iodide with lead solutions, or by combining lead(II) nitrate with potassium iodide, among other methods.
2. Crystal Structure of Lead(II) Iodide
Its hexagonal crystals turn reddish-brown when heated, reverting upon cooling. The structure features a cadmium iodide-type arrangement with defined lattice constants and bond distances.
3. Chemical Reaction of Lead(II) Iodide
Reacts with sodium sulfide to produce lead(II) sulfide, and is susceptible to oxidation, yielding lead oxide and iodine while producing toxic gases when heated.
4. Toxicity of Lead(II) Iodide
Classified as carcinogenic and toxic, lead(II) iodide is subject to stringent regulatory measures to ensure safe handling and use.