Arsenic selenide: what is it? how does it work?

Arsenic selenide is an inorganic compound with the chemical formula As2Se3.

On October 27, 2017, the International Agency for Research on Cancer (IARC) of the World Health Organization (WHO) released a preliminary reference for the list of carcinogens. Arsenic and inorganic arsenic compounds are included in the list of Category 1 carcinogens.

Arsenic selenide physical and chemical properties

Density: 4.75

Melting point: 360 DHS C

Molecular formula: As2Se3

Molecular weight: 390.75500

Accurate mass: 393.62400

Appearance: Black crystal or dark solid

Storage condition: ventilated and dry at low temperature

Stability: insoluble in water, soluble in nitric acid.

Arsenic selenide powder toxicity and ecology

Arsenic selenide toxicological data:

1. Acute toxicity: rat oral LD50: >5gm/kg

Ecological data of arsenic selenide:

It is extremely harmful to water. Even a small amount of the product infiltrates into the ground will cause harm to drinking water. Do not release the product into the surrounding environment without permission. Harmful to organic matter in water.

Arsenic selenide safety information

Hazard Code (Europe) : T: Toxic; N: Dangerous for the environment;

Risk Statement (Europe) : R23/25

Safety Statement (Europe) : 20/21-28-45-61-60

UN No.: UN 1557

RTECS number: CG2285000

Packing grade: II

Danger category: 6.1

Preparation for arsenic selenide

Add 25%(mass fraction) of HCl and stoichiometric ratios of As and Se to 70% by volume in a 3mm diameter quartz ampoule. It is sealed and placed in an autoclave, and distilled water is added to 72% of the volume of the autoclave to ensure adequate internal pressure is generated at the reaction temperature. Then the kettle cover is tightly sealed and placed in a tubular vertical electric furnace, heated to 365 ° C for 3 days, and then gradually cooled at a rate of about 2 ° C /h within 7 days. The temperature gradient shifts the product to the higher temperature region. Acicular crystals grow in the upper part of the ampule. The pressure in the autoclave is 720bar(calculated by space factor 0.70 and temperature 365℃,1bar=105Pa).

The stoichiometric ratio of As and Se were sealed in a quartz ampoule, heated at 600 ° c for 4h under vacuum, and then quenched. Then the glassy substance was annealed at 320℃ for 24h, and then reduced to 280℃ at a rate of 5℃ per day to obtain As2Se3.

Arsenic selenide application

Arsenic selenide is a photosensitive material widely used in the field of electron-photonics.