Nitride

In chemistry, a nitride is a chemical compound of nitrogen. Nitrides can be inorganic or organic, ionic or covalent. The nitride anion, N^3- ion, is very elusive but compounds of nitride are numerous, although rarely naturally occurring. Some nitrides have a found applications,^[1] such as wear-resistant coatings (e.g., titanium nitride, TiN), hard ceramic materials (e.g., silicon nitride, Si₃N₄), and semiconductors (e.g., gallium nitride, GaN). The development of GaN-based light emitting diodes was recognized by the 2014 Nobel Prize in Physics.^[2] Metal nitrido complexes are also common.

Synthesis of inorganic metal nitrides is challenging because nitrogen gas (N₂) is not very reactive at low temperatures, but it becomes more reactive at higher temperatures. Therefore, a balance must be achieved between the low reactivity of nitrogen gas at low temperatures and the entropy driven formation of N₂ at high temperatures.^[3] However, synthetic methods for nitrides are growing more sophisticated and the materials are of increasing technological relevance.^[4]