Adams' Catalyst

Adams' catalyst, also known as platinum dioxide, is usually represented as platinum(IV) oxide hydrate, PtO2-H2O. It is a catalyst for hydrogenation and hydrogenolysis in organic synthesis. This dark brown powder is commercially available. The oxide itself is not an active catalyst, but it becomes active after exposure to hydrogen whereupon it converts to platinum black, which is responsible for reactions.

Read more about Adams' Catalyst:  Preparation, Uses, Development, Safety