Indium(III) hydroxide
Indium(III) hydroxide, also known as indium hydroxide or In(OH)3, is an inorganic compound. It is a white, gelatinous solid, almost insoluble in water. It is amphoteric, meaning it can react with both acids and bases.
Properties:
Indium(III) hydroxide is not well-defined and often exists as a hydrated form, In(OH)3·nH2O. Upon heating, it decomposes to form indium(III) oxide (In2O3). The precise decomposition temperature is variable and depends on the method of preparation and the hydration state of the hydroxide. It readily dissolves in strong acids to form indium(III) salts. It also dissolves in strong bases to form hydroxoindate(III) complexes.
Preparation:
Indium(III) hydroxide is typically prepared by the addition of a hydroxide (e.g., sodium hydroxide or ammonium hydroxide) to a solution containing an indium(III) salt, such as indium(III) chloride (InCl3) or indium(III) nitrate (In(NO3)3). The resulting precipitate is then filtered, washed, and dried. The exact properties of the resulting hydroxide, such as its particle size and hydration state, depend on the reaction conditions.
Uses:
Indium(III) hydroxide has limited direct applications. It is primarily used as a precursor to other indium compounds, especially indium(III) oxide, which is a component in various electronic and optical devices, notably transparent conductive oxides (TCOs) such as indium tin oxide (ITO). It has also been investigated for use in catalysis and as an adsorbent material.
Safety:
Like other indium compounds, indium(III) hydroxide should be handled with care. While the toxicity of indium compounds is generally considered to be low compared to some other metals, chronic exposure can lead to adverse health effects. Appropriate protective measures, such as gloves and eye protection, should be used when handling this compound. More detailed toxicological information should be consulted before working with indium(III) hydroxide.