Adams’s catalyst, also known as platinum oxide, is usually represented as platinum(IV) oxide hydrate, PtO2•H2O. It is a catalyst for hydrogenationand 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.

Adams’s catalyst is used for many applications. It has shown to be valuable for hydrogenation and hydrogenolysis, dehydrogenation, and oxidation reactions. During the reaction, platinum metal (platinum black) is formed which has been cited to be the active catalyst.[3][4]Hydrogenation occurs with syn stereochemstry when used on an alkyne resulting in a cis-alkene. Some of the most important transformations include the hydrogenation of nitro compounds to amines and ketones to alcohols. Although, reductions of alkenes can be performed with Adam’s catalyst in the presence of nitro groups without reducing the nitro group. When reducing nitro compounds to amines, platinum catalysts are preferred over palladium catalysts to minimize hydrogenolysis. The catalyst is also used for the hydrogenolysis of phenyl phosphate esters, a reaction that does not occur with palladium catalysts. The pH of the solvent significantly affects the reaction course, and reactions of the catalyst are often enhanced by conducting the reduction in neat acetic acid, or solutions of acetic acid in other solvents.