Disilane is a

chemical compound A chemical compound is a chemical substance composed of many identical molecules (or molecular entities) containing atoms from more than one chemical element held together by chemical bonds. A molecule consisting of atoms of only one element ...

with general

chemical formula A chemical formula is a way of presenting information about the chemical proportions of atoms that constitute a particular chemical compound or molecule, using chemical element symbols, numbers, and sometimes also other symbols, such as pare ...

Si₂R₆ that was first identified in 1902 by

Henri Moissan Ferdinand Frédéric Henri Moissan (; 28 September 1852 – 20 February 1907) was a French chemist and pharmacist who won the 1906 Nobel Prize in Chemistry for his work in isolating fluorine from its compounds. Among his other contributions, Mo ...

and Samuel Smiles (1877–1953) where R = H. Moissan and Smiles reported disilane as being among the products formed by the action of dilute acids on metal silicides. Although these reactions had been previously investigated by

Friedrich Woehler Friedrich may refer to: Names *Friedrich (given name), people with the given name ''Friedrich'' *Friedrich (surname), people with the surname ''Friedrich'' Other *Friedrich (board game), a board game about Frederick the Great and the Seven Years' ...

and Heinrich Buff between 1857 and 1858, Moissan and Smiles were the first to explicitly identify disilane. They referred to disilane as ''silicoethane''. Higher members of the homologous series formed in these reactions were subsequently identified by Carl Somiesky (sometimes spelled "Karl Somieski") and

Alfred Stock Alfred Stock (July 16, 1876 – August 12, 1946) was a German inorganic chemist. He did pioneering research on the hydrides of boron and silicon, coordination chemistry, mercury, and mercury poisoning. The German Chemical Society's Alfred-Stoc ...

. At

standard temperature and pressure Standard temperature and pressure (STP) or standard conditions for temperature and pressure are various standard sets of conditions for experimental measurements used to allow comparisons to be made between different sets of data. The most used ...

, disilane is a colourless, acrid gas. Disilane and

ethane Ethane ( , ) is a naturally occurring Organic compound, organic chemical compound with chemical formula . At standard temperature and pressure, ethane is a colorless, odorless gas. Like many hydrocarbons, ethane is List of purification methods ...

have similar structures, although disilane is much more reactive. Other compounds of the general formula (X =

hydrogen Hydrogen is a chemical element; it has chemical symbol, symbol H and atomic number 1. It is the lightest and abundance of the chemical elements, most abundant chemical element in the universe, constituting about 75% of all baryon, normal matter ...

halogen The halogens () are a group in the periodic table consisting of six chemically related elements: fluorine (F), chlorine (Cl), bromine (Br), iodine (I), and the radioactive elements astatine (At) and tennessine (Ts), though some authors would ...

alkyl In organic chemistry, an alkyl group is an alkane missing one hydrogen. The term ''alkyl'' is intentionally unspecific to include many possible substitutions. An acyclic alkyl has the general formula of . A cycloalkyl group is derived from a cy ...

aryl In organic chemistry, an aryl is any functional group or substituent derived from an aromatic ring, usually an aromatic hydrocarbon, such as phenyl and naphthyl. "Aryl" is used for the sake of abbreviation or generalization, and "Ar" is used ...

, and mixtures of these groups) are called disilanes. Disilane is a

group 14 hydride Group 14 hydrides are chemical compounds composed of hydrogen atoms and carbon group, group 14 atoms (the elements of group 14 are carbon, silicon, germanium, tin, lead and flerovium). Tetrahydrides The tetrahydride series has the chemical formu ...

Synthesis

Disilane is usually prepared by the

hydrolysis Hydrolysis (; ) is any chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution reaction, substitution, elimination reaction, elimination, and solvation reactions in which water ...

magnesium silicide Magnesium silicide, Mg2Si, is an inorganic compound consisting of magnesium and silicon. As-grown Mg2Si usually forms black crystals; they are semiconductors with n-type conductivity and have potential applications in thermoelectric generators. Cr ...

. This reaction produces

silane Silane (Silicane) is an inorganic compound with chemical formula . It is a colorless, pyrophoric gas with a sharp, repulsive, pungent smell, somewhat similar to that of acetic acid. Silane is of practical interest as a precursor to elemental ...

, disilane, and even trisilane. The method has been abandoned for the production of silane, but it remains viable for generating disilane.Barry Arkles "Silicon Compounds, Silanes" in Kirk-Othmer Encyclopedia of Chemical Technology John Wiley & Sons, New York, 1997. DOI: . The presence of traces of disilane is responsible for the spontaneous flammability of silane produced by hydrolysis by this method (analogously

diphosphine Diphosphane, or diphosphine, is an inorganic compound with the chemical formula . This colourless liquid is one of several binary phosphorus hydrides. It is the impurity that typically causes samples of phosphine to ignite in air. Properties, ...

is often the spontaneously

pyrophoric A substance is pyrophoric (from , , 'fire-bearing') if it ignites spontaneously in air at or below (for gases) or within 5 minutes after coming into contact with air (for liquids and solids). Examples are organolithium compounds and triethylb ...

contaminant in samples of

phosphine Phosphine (IUPAC name: phosphane) is a colorless, flammable, highly toxic compound with the chemical formula , classed as a pnictogen hydride. Pure phosphine is odorless, but technical grade samples have a highly unpleasant odor like rotting ...

). It also arises by

thermal decomposition Thermal decomposition, or thermolysis, is a chemical decomposition of a substance caused by heat. The decomposition temperature of a substance is the temperature at which the substance chemically decomposes. The reaction is usually endothermic ...

disilane via both

photochemical Photochemistry is the branch of chemistry concerned with the chemical effects of light. Generally, this term is used to describe a chemical reaction caused by absorption of ultraviolet (wavelength from 100 to 400 nm), visible (400–750&nb ...

and thermal decomposition of silane. The reduction of with

lithium aluminium hydride Lithium aluminium hydride, commonly abbreviated to LAH, is an inorganic compound with the chemical formula or . It is a white solid, discovered by Finholt, Bond and Schlesinger in 1947. This compound is used as a reducing agent in organic synthe ...

affords disilane in modest yield.

Applications and reactions

Disilane and silane thermally decompose around 640 °C, depositing

amorphous silicon Amorphous silicon (a-Si) is the non-crystalline form of silicon used for solar cells and thin-film transistors in LCDs. Used as semiconductor material for a-Si solar cells, or thin-film silicon solar cells, it is deposited in thin films onto ...

. This

chemical vapor deposition Chemical vapor deposition (CVD) is a vacuum deposition method used to produce high-quality, and high-performance, solid materials. The process is often used in the semiconductor industry to produce thin films. In typical CVD, the wafer (electro ...

process is relevant to the manufacture of photovoltaic devices. Specifically it is utilized in the production of silicon wafers. More generally, diorganosilanes are produced by reductive coupling of silyl chlorides, e.g. : Disilane gas can be used to control pressure of Si vapors during process of

graphene Graphene () is a carbon allotrope consisting of a Single-layer materials, single layer of atoms arranged in a hexagonal lattice, honeycomb planar nanostructure. The name "graphene" is derived from "graphite" and the suffix -ene, indicating ...

growth by

SiC The Latin adverb ''sic'' (; ''thus'', ''so'', and ''in this manner'') inserted after a quotation indicates that the quoted matter has been transcribed or translated as found in the source text, including erroneous, archaic, or unusual spelling ...

. Pressure of Si vapors influences quality of produced graphene.Mishra, N., Boeckl, J., Motta, N. and Iacopi, F. (2016), Graphene growth on silicon carbide: A review. Phys. Status Solidi A, 213: 2277-2289. doi:10.1002/pssa.201600091 (check page 2280)

References

{{Hydrides by group Silanes Industrial gases Substances discovered in the 1900s Pyrophoric materials