Indium Sulfate (In2(SO4)3)-Powder

Characteristic

Indium(III) sulfate (In₂(SO₄)₃) is a sulfate salt of the metal indium. As a solid indium sulfate can be anhydrous, or take the form of a pentahydrate with five water molecules[9] or a nonahydrate with nine molecules of water.

Chemical formula：In₂(SO₄₎₃

Molar mass：517.81 g/mol

Appearance：white-gray odorless powder, hygroscopic, monoclinic crystals

Density：3.44 g/cm³, solid

Melting point：decomposes at 600 °C

Solubility in water：soluble, (539.2 g/L at 20 °C)

Crystal structure：monoclinic

Application

Indium sulfate is a commercially available chemical. It can be used to electroplate indium metal, as a hardening agent in gold electroplating or to prepare other indium containing substances such as copper indium selenide. It has been sold as a health supplement, even though there is no evidence of benefit to humans, and it is toxic.

The first high-frequency transistor was the surface-barrier germanium transistor developed by Philco in 1953, capable of operating up to 60  MHz. These were made by etching depressions into an N-type germanium base from both sides with jets of indium sulfate until it was a few ten-thousandths of an inch thick. Indium electroplated into the depressions formed the collector and emitter.