Sodium hypophosphite, also known as sodium phosphinate or NaPO2H2, is a white crystalline solid typically found as the monohydrate form, NaPO2H2·H2O, and is soluble in water while also readily absorbing moisture from the air.
Its unique ability to convert metal ions back into base metal makes it especially useful in the electroless nickel plating industry. This enables the creation of a durable and robust nickel-phosphorus film even on irregular surface objects in fields such as avionics, aviation, and the petroleum industry.
Sodium hypophosphite is also capable of reducing nickel ions to metallic nickel on metal and plastic substrates, provided the latter is activated using palladium particles. The resulting nickel deposit contains up to 15% phosphorus. Recent studies have even explored its potential use as a food additive.